ML11356A433

Riverkeeper (Riv) Pre-Filed Evidentiary Hearing Exhibit RIV000037, Official Transcript, ACRS Subcommittee, 12/6/2006

ML11356A433
Person / Time
Site:	Indian Point
Issue date:	12/22/2011
From:	Advisory Committee on Reactor Safeguards
To:
SECY RAS
Shared Package
ML11356A432	List: ML11356A433 ML11356A434
References
RAS 21628, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01, NRC-1347 ACRST-3374
Download: ML11356A433 (213)

Text

{{#Wiki_filter:RIV000037 Date Submitted: December 22, 2011 Official Transcript of Proceedings AcliST-Jj7'f NUCLEAR REGULATORY COMMISSION

Title:

Advisory Committee on Reactor Safeguards Subcommittee on Materials, Metallurgy and Reactor Fuels PROCESS USING ADAMS TEMPLATE: ACRS/ACNW-005 Docket Number: (not applicable} SUNS! REVIEW COMPLETE Location: Rockville, Maryland Date: Wednesday, December 6, 2006 Work Order No.: NRC-1347 Pages 1-162

RIV000037 Date Submitted: December 22, 2011

• DISCLAIMER UNITED STATES NUCLEAR REGULATORY COMMISSION'S ADVISORY COMMITTEE ON REACTOR SAFEGUARDS December 6, 2006 The contents of this transcript of the proceeding of the United States Nuclear Regulatory Commission Advisory Committee on Reactor Safeguards, taken on December 6, 2006, as reported herein, is a record of the discussions recorded at the meeting held on the above date .
• This transcript has not been reviewed, corrected and edited and it may contain inaccuracies .

RIV000037 Date Submitted: December 22, 2011 1 1 UNITED STATES OF AMERICA

• 2 3

4 NUCLEAR REGULATORY COMMISSION

                                   + + + + +

ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 5 SUBCOMMITTEE ON MATERIALS, METALLURGY, AND 6 REACTOR FUELS 7 + + + + + 8 WEDNESDAY, 9 December 6, 2006 10 + + + + + 11 The meeting was convened in Room T-2B3 of 12 Two White Flint North, 11545 Rockville Pike, 13 Rockville, Maryland, at 1:30 p.m., Dr. J. Sam Armijo, 14 Chairman of the subcommittee, presiding. 15 MEMBERS PRESENT: 16 J. SAM ARMIJO, CHAIRMAN 17 MARIO V. BONACA, ACRS MEMBER 18 SAID ABDET KRALIK, ACRS MEMBER 19 SANJOY BANERJEE, ACRS MEMBER 20 THOMAS S. KRESS, ACRS MEMBER 21 JOHN D. SIEBER, ACRS MEMBER 22 GRAHAM WALLIS, ACRS MEMBER 23 CHARLES G. HAMMER, DESIGNATED FEDERAL OFFICIAL 24 CAXETANO SANTOS, ACRS STAFF 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 2 1 I N D E X

• 2 Opening Remarks, S. Armijo, ACRS 3 3 Overview of Regulatory Guide 1.207 (DG-1144) 4 H. Gonzalez, RES 4 5 Discussion of Technical Basis for Regulatory 6 Guide 1.207 and NUREG/CF-6909, 0. Chopra, 7 Argonne National Laboratory 11 8 Discussion of Public Comments and Staff 9 Responses for Regulatory Guide 1.207 10 and NUREG/CR-6909, H. Gonzalez, RES and 11 0. Chopra, ANL 77 12 ASME Presentation, E. Ennis, ASME 85 13 AREVA Presentation, D. Cofflin, AREVA 142 14 Adjourn 161 15 16 17 18 19 20 21 22 23 24 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005*3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 3 1 P-R-0-C-E-E-D-I-N-G-S

• 2 1:31 P.M.

3 CHAIRMAN ARMIJO: The meeting will now 4 come to order. This is a meeting of the Materials, 5 Metallurgy and Reactor Fuels Subcommittee. My name is 6 Sam Armijo, Chairman of the Committee. ACRS Members 7 in attendance are Dr. Mario Bonaca, Mr. Jack Sieber, 8 Dr. Bill Shack is sitting as a member of the audience 9 or staff at this point, Dr. Thomas Kress and Dr. 10 Graham Wallis are also present. 11 Gary Hammer of the ACRS staff is the 12 Designated Federal Official for this meeting. 13 The purpose of this meeting is to discuss 14 Regulatory Guide 1. 2 07, guidelines for evaluating 15 fatigue analyses incorporating the life reduction of 16 metal components due to the effects of light-water 17 reactor environments for new reactors. We will hear 18 presentations from the NRC's Office of Nuclear 19 Regulatory Research and their contractor, Argonne 20 National Laboratory. 21 We will also hear presentations from 22 representatives of the American Society of Mechanical 23 Engineers and AREVA. 24 The Subcommittee will gather information, 25 analyze relevant issues and facts, and formulate NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 4 1 proposed positions and actions, as appropriate for

• 2 3

4 deliberation by the Full Committee. The rules for participation in today' s meeting have been announced as part of the notice of

  *5 this       meeting previously published                 in   the   Federal 6 Register.        We have received no written comments from 7 members of the public regarding today's meeting.

8 A transcript of the meeting is being kept 9 and will be made available as stated in the Federal 10 Register notice. Therefore, we request that 11 participants in this meeting use the microphones 12 located throughout the meeting when addressing the 13 Subcommittee . 14 Participants should first identify IS themselves and speak with sufficient clarity and 16 volume so that they may be readily heard. 17 We will now proceed with the meeting and 18 I call on Mr. Hipolito Gonzales of the Office of 19 Nuclear Regulatory Research to begin. 20 MR. GONZALEZ: Thank you. I am Hipolito 21 Gonzalez. I'm the Project Manager for Regulatory 22 Guide 1.207. I'm from the Corrosion and Metallurgy 23 Branch and with me, Omesh Chopra. He's from Argonne 24 National Lab. He's going to be presenting part of the 25 regulatory basis, technical regulatory basis. NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 5 1 I would like to acknowledge William Cullen

• 2 3

4 from the Office of Research and John Ferrer, NRR, for their helpful reviews and comments on this project. Next slide. 5 The agenda today, we're going to be 6 discussing Regulatory Guide 1.207. I'm going to give 7 a quick historical perspective and then we're going to 8 go over an overview the reg. guide. And then Omesh

  .9 will present the technical basis which is the NUREG 10  report CR, NUREG CR 6909, Revision 1.

11 I'm going to give a summary of the 12 regulatory positions. And the last presentation is 13 going to be the resolution of public comments . 14 The ASME Section 3, fatigue design curves 15 were developed in the late 1960s and the early 1970s. 16 The tests conducted were in laboratory environments at 17 ambient temperatures. And the design curves included 18 adjusted factors of 2 constraint and 20 on cyclic life 19 to account for variations in materials, surface 20 finish, data scatter and size. 21 Results from the studies in Japan and 22 others in ANL, Argonne National Lab, as illustrated. 23 Potential significant effects of the light-water 24 reactor coolant environment on the fatigue life of the 25 steel, steel components. NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 6 1 Next slide.

• Since the late 1980s, the NRC staff has 2

3 been involved in the discussion with ASME co-corrunittees, the PVRC and Technical Corrununi ty to 5 address the issues related to the environmental 6 effects on fatigue. 7 In 1991, the ASME Board of Nuclear Code 8 and Standards requested the PVRC to examine worldwide 9 fatigue strain versus like data and develop 10 recorrunendations. 11 In 1995, it was resolution for GSI 166 12 which established that the risk to core damage from 13 fatigue failure of the reactor coolant system was 14 small. So no action was required for current plant 15 design life of 40 years. Also, the NRC staff 16 concluded that fatigue issues should be evaluated for 17 extended period of operation for license renewal and 18 this is under GSI-190. 19 In 1999, we had GSI-190 and the fatigue 20 evaluation of metal components for 60-year life plant, 21 plant life. Staff concluded that consistent with 22 requirements of 10 CFR 54.21, that aging management 23 programs for license renewal should address components 24 of fatigue including the effects of the environment . 25 On December 1, 1999, by letter to the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011

                                                                                   .7 1 Chairman        of   the   ASME     Board      of     Nuclear    Code       and

• 2 3

4 Standards, the NRC requested ASME to revise the code to include the environmental effects on the fatigue design components. 5 Next slide. 6 ASME initiated the PVRC Steering Committee 7 on cyclic life and environmental effects and the PVRC 8 Committee recommended revising the code for design 9 fatigue curves. This was to WRC Bulletin 487. 10 After more than 25 years of deliberation, 11 there hasn't been any consensus regarding 12 environmental effects on fatigue life on the light-13 water reactor environments . 14 The NRR requested research under user need 15 requests to 504 to develop guidance for determining 16 the acceptable fatigue life of ASME pressure boundary 17 components with consideration of the light water 18 reactor environment and this guidance will be used for 19 supporting reviews of application that the Agency 20 expects to receive for new reactors. The industry was 21 immediately notified that the NRC staff initiated this 22 work, the development of the reg. guide. In addition, 23 this is one of the high priority reg. guides to be 24 completed by March 2007 . 25 In February and August this year, NRC NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 8 1 staff and ANL, we had presented at the ASME Code

• 2 3

4 Meetings the technical basis draft, NUREG CR6909. July 24, 2006, both the draft reg. guide and the NUREG technical basis report were published for public On 5 corrnnents and the public corrnnent period ended September 6 25. 7 In addition, on July 25, ANL presented a 8 paper on the technical basis again. 9 CHAIRMAN ARMIJO: Just to clarify 10 something, new reactors, does that include -- do these 11 rules apply to already certified design, such as the 12 ABWR and the AP1000? Are they grandfathered by virtue

 ~3 of their certification?

14 MR. FERRER: This is John Ferrer from NRR 15 staff. They're grandfathered by virtue of their 16 certification that's already been addressed in the 17 reviews there, so we're not backfitting this reg. 18 guide to those certified designs. 19 DR. SIEBER: For 40 years though. 20 CHAIRMAN ARMIJO: Well, actually, if you 21 read the safety evaluation, the way it was written 22 said that they were evaluated for 60 years. 23 DR. SIEBER: Okay. 24 CHAIRMAN ARMIJO: That's kind of an 25 inconsistency in a way because they haven't been built NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 9 1 in the United States and if they were being certified

• after this reg. guide is issued, that would be the 2

3 rule -- that would control the design, wouldn't it? 4 MR. FERRER: I wish I -- I agree with you. 5 Unfortunately, the way certified design works is once 6 we certify it, we'd have to go through a backfi t 7 evaluation if we were going to apply this. And what 8 happened in the backfit evaluation, if you go back a 9 couple of slides on the GSI-166 and the GSI-190, we 10 did a backfit evaluation and showed the risk was not 11 high enough to justify a backfit, but the reason we 12 implemented it on license renewal was the fact that 13 the probability of leakage increased significantly 14 within 40 and 60 years. 15 But again, the risk which is the 16 probability of getting a pipe rupture that would lead 17 to core damage was still low. 18 CHAIRMAN ARMIJO: Thank you. 19 MR. GONZALEZ: Now I am going to go to an 20 overview of the reg. guide. 21 Next slide. 22 How the reg. guide 1.207 relates to the 23 regulatory requirements. GDC criterion, general 24 design criterion 1, quality standards and waivers . 25 And the part says that safety-related systems, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 10 1 structures and components must be designed,

• 2 3

4 fabricated, erected and tested to the quality standard commensurate function performed. with the importance of the safety 5 GDC-30 states, in part, that components 6 included in a reactor pressure boundary must be 7 designed, fabricated, erected and tested to the 8 highest practical quality standards. 9 In 10 CFR 50.55A endorses the ASME boiler 10 pressure vessel code for design of safety-related 11 systems and components. These are Class 1 components. 12 ASME Code Section 3 includes the design 13 fatigue, includes the fatigue design curves. But 14 these fatigue design curves do not address the impact 15 of the reactor coolant system environment. 16 The objective of this regulatory guide is 17 to provide guidance for determining the acceptable 18 fatigue life of ASME pressure boundary components with 19 the consideration of the light water reactor 20 environment for major structural materials that will 21 be carbon steel, low-alloy steels, austenitic 22 stainless steel and nickel-based alloys. For example, 23 alloy-600, 690. 24 So in this guide, describes an approach 25 that the NRC staff considers acceptable to support NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 11 1 reviews about the applications that the Agency expects

• 2 3

4 to receive for new reactors . new plants. Implementation, this will only apply to And no backfitting is intended. And this 5 is due to the conservatism in the current fleet of 6 reactors because of the design practices for fatigue 7 work conservatisms all plants were designed. 8 Next slide, please. 9 Now I'm going to how the technical 10 basis was developed. Omesh is going to give the 11 presentation on the technical basis report. 12 MR. CHOPRA: Thanks, Hipo. 13 DR. BONACA: I have a question regarding 14 your last statement. No backfitting is intended, 15 conservatism on coolant reactors. If the approach was 16 conservative on coolant reactors, I mean could it be 17 used also for new reactors? 18 MR. FERRER: Let me try to answer that. 19 In reviewing GSI-166 which was backfit to current 20 operating plants, we evaluated the as-existing fatigue 21 analyses and there were a number of conservatisms in 22 the specification of transients and the methodology 23 and the analysis. 24 We don't know whether or not that same 25 conservatism will be applied in the new reactors. In NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 12 1 addition, there have been some changes in the ASME

• 3 4

code criteria since those original analyses were done that analysis. removed some of the conservatisms So if somebody were to do code analysis to in the 5 the current code criteria may not have the same level 6 of conservatisms. 7 DR. BONACA: I understand. Thank you. 8 MR. CHOPRA: The issue we are discussing 9 here today is effect of light water reactor coolant 10 environments on the fatigue life of structural steels. 11 Over the last 20 to 30 years, there's been sufficient 12 data accumulated, both in the U.S. and worldwide, 13 especially in Japan, which shows that coolant 14 environments can have a significant effect on the 15 fatigue life of these steels. 16 And this data is very consistent. It 17 doesn't matter where it has been rated, all show 18 similar trends without any exception. And also, the 19 fatigue data is consistent with a much larger database 20 on fatigue crack growth rates affect on environment of 21 fatigue crack growth rates. There's no inconsistency. 22 The mechanisms are very similar and both show similar 23 trends, effects of radius parameters, material loading 24 and environmental parameters have similar inference on 25 fatigue crack initiation and fatigue crack growth. NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

RIV000037 Date Submitted: December 22, 2011 13 1 And this fatigue data has been evaluated

• 2 4

to clearly define which are the important parameters .

 -3 * * **They're well parameters defined and* also for    which the environmental range *of* these effects          are 5       significant, it's clearly defined.

6 So we know the conditions under which 7 environment would have an effect on fatigue life. The 8 question is do these conditions exist in the fleet? 9 If they exist, we will have an effect on the 10 environment and it should be considered. We know from 11 subsection 31.32.21 that the current fatigue design 12 curves do not include the effect of aggressive 13 environment which can accelerate fatigue failures and 14 has to be considered. 15 So the burden is on the designer to better 16 define these transients, to know what conditions 17 occurred during these transients and whether 18 environment would be involved. 19 Next, before getting into the 20 environmental effects, I just want to cover a few 21 background information. We are talking about the 22 effect of environment on fatigue life. Let's 23 understand what do we mean by fatigue life? The 24 current code design curves were based on data which 25 was where the specimens were tested to failure. Quite NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

14 1 often, these design curves are termed as failure 2 codes, but I think the intent was to define fatigue 3 life as to prevent fatigue crack initiation, because 4 the data which has been obtained in the last 20 to 30 5 years in these results fatigue life is defined as the 6 number of sitings for the peak load to decrease by 25 7 percent. 8 And for the type of specimen, size of 9 specimens used in these tests, mostly quarter inch or 10 three-eighth round cylindrical specimens, this would 11 correspond to creating a three millimeter crack. So 12 we can say the fatigue life is the number of cycles 13 for a given strain condition to initiate a three 14 millimeter crack and from several studies we know that 15 surface crack, about 10 micron deep form quite early 16 during fatigue cycling. 17 So we can say that fatigue life is nothing 18 but it's associated with growth of these cracks from 19 a 10 micron size to 3 millimeter size and typically 20 this is the behavior of the growth of these cracks is 21 in this shape where crack length is a fraction of 22 fatigue life varies like this and it's divided into 23 two stages, initiation stage and a propagation stage. 24 Initiation stage is characterized by decrease in crack

• 25 growth rates. It's very sensitive to micro structure.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

15 1 It involves sheer crack growth which is 45 degrees to 2 the stress axis, whereas propagation stage is not very 3 sensitive to microstructure. It was tensile crack 4 growth which is perpendicular to the stress axis and

  *5 this       is   the   stage where you            see on      the   fracture 6 surface well defined striations.

7 Various studies have shown that this 8 transition from an initiation stage to a propagation 9 stage occurs around -- depending on the material, 150 10 micron or 300 micron, that range. 11 So initiation stage is growth of crack up 12 to 300 microns. Propagation stage is beyond that to 13 3000 or 3 millimeter size . 14 Next slide. 15 CHAIRMAN ARMIJO: Before you leave that 16 curve, just for the benefit of people who don't 17 understand these curves, what is the time difference 18 between or the fatigue life difference from the three 19 millimeter crack initiated crack to through-wall 20 failure in the case of let's say a one-inch pipe, one-21 inch wall thickness? 22 MR. CHOPRA: We would use the crack growth 23 rate data. 24 CHAIRMAN ARMIJO: Would that typically

• 25 increase the number of cycles by a factor of 2 or a NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

16 1 factor of 10? 2 MR. CHOPRA: It depends on the conditions, 3 loading conditions and environment and so on. So we 4 know what the crack growth rates are for various 5 conditions. So we have to use that. But maybe I can 6 answer another way. In a test specimen, the 7 difference between 25 percent load drop and complete 8 failure of a specimen is very small. It's less than 9 one or two percent. 10 So whether we call it failure of a 11 specimen or defining it 25 percent drop, would be very 12 small difference. The idea of using 25 percent load 13 drop was to be consistent so that we define life as 14 some consistent -- all the labs do the same thing. So 15 that was the idea. 16 Otherwise, for a real component, if we 17 deal with three millimeter steel in a tube, it would 18 depend on crack growth rates. 19 CHAIRMAN ARMIJO: Okay. 20 MR. CHOPRA: Now the same curve I 've 21 plotted a slightly different way where I plotted still 22 our cracked growth rates was the crack depths, 23 decreasing growth rates in the initiation stage and 24 increasing growth rates .

• 25 Now of course, crack growth would depend NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

17 1 on applied stress ranges. The higher the stress 2 range, the higher the crack growth. The delta sigma 3 one at very low stresses, the cracks which form during 4 cyclic loading may not growth to large enough size 5 that they can -- the propagation stage takes over. 6 DR. WALLIS: Crack velocity is really 7 growth rate and microns per cycle, not per unit of 8 time. 9 MR. CHOPRA: Right, but depending on the 10 time period one could convert it to 11 DR. WALLIS: I know, but velocity is a 12 strange word. 13 MR. CHOPRA: Yes, maybe this should be 14 crack growth rate. 15 DR. WALLIS: If there's no cycling, 16 there's no crack growth. 17 MR. CHOPRA: Yes, yes. Beta sigma one, 18 when the stresses are very low, cracks may grow to 19 large enough size for the propagation to take over and 20 this is known as the fatigue limit of the material. 21 This is true for constant loading. 22 MR. BANERJEE: What's the mechanism that 23 changes the velocity so much? 24 MR. CHOPRA: Initial sheer crack growth.

• 25 It will extent maximum couple of degrees.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. So it's a (202) 234*4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

18 1 sheer crack growth, 45 degrees, whereas, once you go 2 deep enough, large enough size, you get into a 3 different process where actually fracture mechanics 4 methodology can be used to express that. It's a 5 tensile crack growth. 6 MR. BANERJEE: It's a multi-grain sort of 7 size and then it starts -- a different mechanism. 8 MR. CHOPRA: Typically, a couple of 9 grains. Fatigue limit is applicable only under 10 constant stress conditions. If we have random 11 loading, as in the case of a real component, then we 12 can have situations where we have higher stresses, few 13 cycles of higher stresses, where cracks can grow 14 beyond this depth that you can grow even at stresses 15 which are much lower than fatigue limit. 16 So the history of cycling is also 17 important for evaluating fatigue damage. 18 DR. WALLIS: Delta sigma is the magnitude 19 of this? 20 MR. CHOPRA: Of the stress range, applied 21 extracted stress range. And environment also. 22 DR. WALLIS: Does it matter if it's 10 23 silo or compressible? 24 MR. CHOPRA: On the tests which are used

• 25 for obtaining fatigue data, the strain range ratio is NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202} 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

19 1 -1, completely reversed. So we go from tensile to 2 compressive. 3 Even in environment, corrosion processes 4 can cause the cracks to grow beyond this and then 5 propagation can take over. So environment also could 6 accelerate. So the question is which part -- which of 7 these stages is affected by environment? Initiation 8 or propagation, or both? 9 DR. WALLIS: Your scales are linear, are 10 they? 11 MR. CHOPRA: This is a schematic. 12 DR. WALLIS: Schematic. 13 MR. CHOPRA: This portion is plotted here 14 where I have actual numbers. And I just wanted to 15 show you that we know from crack growth studies that 16 crack growth rates are affected by environment and 17 it's very well documented. 18 DR. WALLIS: These data look unreasonably 19 well behaved for materials data. 20 (Laughter.) 21 MR. CHOPRA: If we plotted a few tests, we 22 will see this happen. 23 CHAIRMAN ARMIJO: Agreement is log, log. 24 DR. WALLIS: Even so, I mean.

• 25 MR. CHOPRA: Anyway, effect of environment NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

20 1 is also, has been studied in fatigue crack initiation. 2 DR. WALLIS: These are real data? 3 MR. CHOPRA: These are real data. But we 4 have calculated the crack growth rates in the fatigue 5 samples by benchmarking the fatigue crack front at 6 different stages during fatigue life. And so we can 7 see the three environments here: high oxygen -- high 8 dissolved oxygen water; low dissolved oxygen; PWR 9 water and air. And we see if you take 100 micron 10 crack length and air-- it took about 3,000 cycles to 11 reach that. In water, it took only 40 cycles, which 12 gives me an average growth rate of 2. 5 micron per 13 cycle and this is this region here, average of this . 14 In this case, it's .0033 microns per 15 cycle. So we see two orders of magnitude effect of 16 environment which suggests that even the initiation 17 stage may be affected even more than what crack growth 18 rate is affected. 19 I just wanted to show you that both stages 20 are affected by the environment, even the growth of 21 very small cracks. 22 Now next, the design curves, what do the 23 design curves -- 24 DR. WALLIS: Presumably, this is not just

• 25 one batch of data like this.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

21 1 MR. CHOPRA: There's lots of data. I'm 2 just giving 3 DR. WALLIS: There's a whole lot of data. 4 MR. CHOPRA: I'm just giving you one set, 5 yes. There's a lot of data. 6 DR. WALLIS: Because if there were 7 uncertainty in these, these curves might switch 8 positions. 9 MR. CHOPRA: sure, but I'm just presenting 10 that data to show that environment has a large effect. 11 It's the relative difference between air and water 12 which I was trying to show, not absolute crack growth 13 rates, just to show that it took only 40 cycles in 1,4 high oxygen water compared to 3,000 which suggests 15 that environment has a large effect on fatigue crack 16 initiation. 17 Now the design curves, we have -- the data 18 which we have obtained is on small specimens. They 19 are absolutely smooth and they were tested in room 20 temperature air. This is what was used to generate 21 the design curves in the current code. And all of 22 them were tested under strain control, fully reversed, 23 strain ratio of -1. 24 Now this gives me the best behavior of a

• 25 specimen when a crack would NEAL R. GROSS be COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

initiated in a (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

22 1 specimen. To apply those results to actual reactor 2 component we need to adjust these results to account 3 for parameters or variables which we know affect 4 fatigue life, but are not included in this data. And 5 these variables are mean stress, surface finish, size, 6 loading history. 7 DR. WALLIS: Does the humidity of the air 8 make a difference?

  *9                    MR. CHOPRA:       Actually, if you look at the 10  basis        document   of     the    current        code,   they     use       a 11  subfactor        which      included       surface       roughness          and 12  environment and by that environment they meant a lab, 13  well-controlled lab environment .

14 DR. WALLIS: Does the humidity of the air 15 make a difference? 16 MR. CHOPRA: In some cases it would, but 17 again, that is not studied as a-- it's not addressed 18 as an explicit parameter in defining fatigue life. 19 All data which was used was room temperature air to 20 generate the design curves. 21 DR. WALLIS: Room temperature means 2 0 22 degrees Centigrade or something? 23 MR. CHOPRA: Yes, 25, yes. To account for 24 these other variables like mean stress, surface

• 25 roughness and so on, what the current code --

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

23 1 DR. WALLIS: I'm sorry, when you maybe 2 you just said it. When you say PWR water, you mean at 3 room temperature or -- 4 MR. CHOPRA: No, no. The design curves do 5 not address environment at all. 6 DR. WALLIS: But your data that you showed 7 us, the well-behaved data. 8 MR. CHOPRA: Those are higher 9 temperatures. 10 DR. WALLIS: Those are higher 11 temperatures. 12 MR. CHOPRA: They would be at reactive 13 temperatures . 14 DR. WALLIS: Okay. Could be a temperature 15 effect as well as an environment effect? 16 MR. CHOPRA: There is and I'll come to 17 that actually. In water, temperature is a very 18 important parameter. And to convert this data on 19 specimens to a real component, what the current code 20 does now is take the best 21 DR. WALLIS: Is the PWR water that is 22 borated at initial strength or something? 23 MR. CHOPRA: PWR is. It both has boron 24 and lithium .

• 25 DR. WALLIS: There's some sort of average NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

24 1 condition throughout the cycle? 2 MR. CHOPRA: Right, right. Typically, 3 people test around 1,000 ppm boron and 2ppm lithium. 4 To adjust these curves to an actual 5 reactor component, what the code does is we take the 6 best of the specimen data and adjust it for mean 7 stress correction and then apply these adjustment 8 factors of two on stress. We decrease the specimen 9 curve by a factor of two on stress and 20 on life, 10 whichever is the lower gets the design curve. But as 11 I mentioned, it does not include the effect of an 12 aggressive environment. In this case, what we are 13 talking about is light-water reactor environments . 14 Now to summarize some of the effects of 15 environment on carbon and low-alloy steels, there are 16 several parameters which are important. Steel type, 17 all of the data shows irrespective of steel type, it 18 doesn't matter which grade of carbon steel or low-19 alloy steel, effect of environment is about the same. 20 There is a strain threshold below which environments 21 do not -- environmental effects do not occur. And 22 this threshold is very close to slightly above the 23 fatigue life of the steel. Strain rate is an 24 important parameter. There is a threshold, 1 percent

• 25 per second above that. Environmental effects are more NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

25 1 great and lower the strain rate, higher the effect. 2 And it diffuses the saturation at around .001 percent

  '3 per second.

4 Similarly, temperature is very important. 5 Once again, there is a threshold; 150 degree C. 6 Higher temperatures, there's greater effect. Below 7 150 -- 8 DR. WALLIS: Strain rate's lowest point is 9 .001 percent a second makes a difference? 10 MR. CHOPRA: Yes. I'll show you some of 11 the results. 12 DR. WALLIS: Really? That's awfully slow, 13 isn't it? 14 MR. CHOPRA: Some of the transients are. 15 DR. WALLIS: Abnormally slow. 16 MR. CHOPRA: Temperature also, there is 17 only a moderate effect below 150. Typically, when I 18 mean moderate effect, up to a factor of 2. Any water 19 touched surface may have up to a factor of 20 DR. WALLIS: Linear decrease doesn't tell 21 me how fast it is. Linear decrease in life after 150 22 doesn't tell me how rapidly it decreases. 23 MR. CHOPRA: There are some slides, I'll 24 show you how much of a different it is .

• 25 MR. SANTOS: Do you have an equation?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

26 1 MR. CHOPRA: Yes. 2 DR. WALLIS: Which goes right through the 3 data? 4 MR. CHOPRA: Absolutely. 5 DR. WALLIS: Is this an Argonne equation 6 or a universal equation? 7 CHAIRMAN ARMIJO: You'll see. 8 DR. WALLIS: We'll see, okay. 9 MR. CHOPRA: Dissolved oxygen is also 10 similar. There's a threshold. In this case, low 11 oxygen environmental effects on carbon low-allow 12 steels are less. There's a threshold .04 ppm. Higher

• • 13 14 15 dissolved oxygen saturates around .05 ppm.

DR. WALLIS: has an environmental How much sulfur is there in effect, 16 the reactor? 17 CHAIRMAN ARMIJO: That's in the steel. 18 DR. WALLIS: In the steel, I'm sorry. I 19 thought you were talking about the environment. Now 20 you're talking about the steel? 21 MR. CHOPRA: These are 22 DR. WALLIS: Dissolved oxygen in the 23 steel. 24 MR. CHOPRA: These are loading parameters .

• 25 Some are environmental parameters.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. Some are material (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

27 1 parameters.

    *2                     DR. WALLIS:        Okay.

3 MR. CHOPRA: Sulfur also has a large 4 effect on fatigue crack initiation. 5 DR. WALLIS: There's no other effects, 6 copper and stuff like that? There's no other effects? 7 MR. CHOPRA: In the steel? No. At least 8 the ones which we have looked at. Sulfur is the one 9 because it deals with the mechanism. Actually, the 10 reason why these are higher for carbon and low-allow 11 steels which these are very well documented. It's the 12 sulfite iron density of the cracking. If we reach a 13 critical sulfite iron density crack enhancement 14 occurs. So these are very well documented in the 15 data. This is a mechanism. That's why sulfur is 16 important. 17 Roughness effects, we know if we have a 18 rough specimen surface it provides sites for 19 initiation. Life goes down. And in carbon low-alloy 20 steel, in air, there is an effect of surface 21 roughness, but some limited data suggests that in 22 water, rough and smooth specimens have about the same 23 life. So roughness effects may not be there for

• -: 24 25 carbon low-alloy steel.

Flow rate also, most of the data has been NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

28 1 obtained on very low flow . rates or semi-stagnant 2 conditions. If we do these tests in higher flow 3 rates, effect of the environment does go down. Means 4 fatigue life would increase in high flow rates by a 5 factor of about 2. 6 Similarly, the effects on austenitic 7 stainless steels, same parameters, steel type, again 8 different grades of austenitic stainless steel, 9 similar effects and even cast austenitic stainless 10 steel have similar effects on the environment. 11 Once again we see a strain threshold below 12 which there is no effect and it's very close to the 13 fatigue limit. The dependence of strain rate and 14 temperature are very similar to what we see in carbon 15 and low-alloy steels. 16 The next three, dissolved oxygen, surface 17 roughness and flow rate, the effects are very 18 different from carbon and low-alloy steels. In this 19 case, for austenitic stainless steel, it's the low 20 oxygen which gives you a larger effect. And 21 irrespective of what steel type we use or what heat 22 treatment, heat treatment that means sensitization. 23 Sensitized stainless steel or solution in the 24 stainless steel both show similar life in low oxygen .

• 25 DR. WALLIS: That extends down to zero NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

29 1 oxygen? 2 MR. CHOPRA: Pardon me? DR. WALLIS: That extends down 4 MR. CHOPRA: If we can achieve that, you 5 know, but typically in a PWR, we have around -- it's 6 a low less than 50 ppm. 7 Yes, low oxygen, irrespective of the steel 8 type or heat treatment, there's a large effect on 9 environment, but in high oxygen, non-water chemistry, 10 PWR conditions, some steels show less effect and these 11 are solution annealed high-carbon steels which are not 12 sensitized. All low carbon grades such as 316 nuclear 13 grade or 304 L may have less effect in high oxygen . 14 Surface roughness and this is both in air 15 and water environments, there's a reduction in life. 16 Even in water. In carbonate steel we did not see a 17 reduction in life for rough samples. In this case, 18 both in air and water there is an effect of roughness. 19 And flow rate, there is no effect of flow rate on 20 fatigue life for austenitic stainless steels in water. 21 The differences between these three 22 suggests that the mechanism may be different for 23 austenitic stainless steels compared to carbon and 24 low-alloy steel. I mention the mechanism for carbon

• 25 and low-allow steels, the sulfite iron density of the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

30 1 crack depth. In this case, it's not well known 2 there's no agreement on what is the mechanism. One 3 possible mechanism would be that as we expose stress 4 surface, hydrogen is created which changes the 5 definition of behavior and of the crack depth. But 6 this is one possible mechanism. 7 The next slides are details of what I 8 summarized. Unless there are specific questions, I'm 9 going to skip these next eight slides which basically 10 give the data which I summarized in the previous. 11 CHAIRMAN ARMIJO: I think it would be 12 better if you just highlight these things, just to 13 make the key points from these charts because I think 14 they're important. 15 MR. CHOPRA: This is the strain rate 16 effect. You were asking about the strain rate. I 17 plotted fatigue life for low-alloy steel, carbon steel 18 under certain conditions, strain amplitudes. In air, 19 PWR water and BWR. 20 DR. WALLIS: Are you claiming there's a 21 significant difference between air and PWR? 22 MR. CHOPRA: It's up to about a factor of 23 2 and this could be a factor of 15 or 20 lower 24 DR. WALLIS: We're not going to put in

• 25 that much oxygen, are we?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

31 1 MR. CHOPRA: BWR has 2 0 0 to 3 0 0 ppb oxygen 2 and in this case, there are correlations which will 3 tell you how much depending on the oxygen, what 4 would be the effect. 5 This is the maximum effect because this is 6 I think . 7. Saturation is at .5. So this is the 7 maximum effect under these conditions. 8 This is strain threshold which I 9 mentioned, the threshold about which effect of 10 environment is there. This gives you dissolved oxygen 11 at .04, this is carbon steel, higher oxygen levels, 12 things go down. And again, in PWR there's only a 13 modern effect . 14 I mentioned that for stainless steel, the 15 effect of dissolved oxygen is different. Here, this 16 is now three or four stainless at two different 17 strainless amplitude. There are two different tests 18 at different conditions, .25 and .33 and high oxygen, 19 no effect upstream rate and low oxygen, it goes down. 20 Whereas, a 316 NG or low carbon grade shows some 21 reduction in life in high oxygen, but not at the same 22 extent as you see in low oxygen. 23 So these are just a few examples I'm 24 showing. There's a lot of data in Japan and Europe

• 25 which shows similar trends.

NEAL R. GROSS This shows the effect of COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202} 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

     /'

32 1 sensitization. Sensitization is defined as a number, 2 EPI number. Degree of sensitization is increasing and 3 same conditions. In air, low oxygen, high oxygen and 4 we see in high oxygen it decreases with degree of 5 sensitization. 6 Effect of -- this is temperature again at 7 150 and lower, depending on what are the strain rates 8 and what are the dissolved oxygen conditions. If it's 9 very low, no effect. These are low oxygen conditions, 10 no effect. High oxygen, depending on the strain rate 11 and dissolved oxygen levels to the extent of the 12 effect in pieces. 13 DR. WALLIS: You're just talking about a 14 hundred cycles there, failure. 1,5 MR. CHOPRA: No, a thousand. In some 16 cases in the environment, it is. 17 DR. WALLIS: Right. 18 MR. CHOPRA: There is up to a factor of 20 19 reduction in life. 20 Surface roughness again, stainless steel*, 21 open circles, smooth specimens; closed circles are 22 symbols are rough samples. A factor of 3 in air, 23 factor about the same in water. 24 CHAIRMAN ARMIJO: I don't want to belabor

• 25 this, but I looked at these data and the one that NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

33 1 shows -- the curve on the left for the air data, the 2 right triangles. They don't go through the best fed 3 curve at all. 4 MR. CHOPRA: Actually, this is 316 NG. 5 316 NG has a steeper slope, but for convenience we are 6 using a curve for all steels. 7 CHAIRMAN ARMIJO: So that's the best fit 8 curve there is for all -- 9 MR. CHOPRA: All stainless steels, all

 ~0 grades, including high or low-carbon grades.

11 DR. WALLIS: The purpose of the ASME curve 12 is to be below all the data, is that the idea? 13 MR. CHOPRA: Once we take into account, 14 you know I mentioned those adjustment factors of 20 on 15 fatigue and 2 on stress. Once we take that into 16 account, once we do that adjustment, then we want to 17 make sure that we are above that. 18 But these are best fit curves. So they 19 give you the average behavior for all -- 20 DR. WALLIS: The ASME code has a factor of 21 2 in it or something? I don't see that. 22 MR. CHOPRA: I'll come to that. Give me 23 a 24

• 25 DR. WALLIS: Okay.

NEAL R. GROSS But the factor of 2 is COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. {202) 234*4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

34 1 in this curve here? 2 MR. CHOPRA: No, these are -- 3 CHAIRMAN ARMIJO : ASME codes . 4 MR. CHOPRA: The code curve has the factor

 *5 of 2.

6 DR. WALLIS: No safety factor. 7 MR. CHOPRA: This is the best fit. These 8 are showing that even -- 9 DR. WALLIS: Oh, I see. So you've give up 10 your margin of 2? 11 MR. CHOPRA: Right. 12 DR. WALLIS: Okay. 13 MR. CHOPRA: What we are saying is only 14 the margin or adjustment factors are gone for the -- 15 CHAIRMAN ARMIJO: That's it. 16 MR. CHOPRA: Environment has taken care of 17 all that and still be within bound for a lot of other 18 factors like surface roughness and so on. 19 DR. WALLIS: You're going to tell us what 20 you're going to do about that? 21 MR. CHOPRA: Sure. 22 DR. WALLIS: Okay. 23 (Laughter.) 24 CHAIRMAN ARMIJO: Absolutely.

• 25 MR. CHOPRA: This gives you the effect of NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

35 1 flow rate. I mentioned that .for carbon and low-alloy 2 steels, effect of environment is less. 3 Now a few slides for nickel alloy. 4 There's much less data on nickel alloys. Here, I've 5 plotted the data which is available -- 6 DR. WALLIS: Much less data. So you're 7 showing us more than you showed us for steel? 8 MR. CHOPRA: What we do is rather than 9 coming with a new curve for nickel alloys, unless we 10 have enough data, what I'm trying to show is that we 11 can use the austenitic stainless steel to represent 12 the nickel alloys and even the few data we have for 13 alloy 690 suggests that we can use the austenitic 14 stainless steel code to determine usage factors, 15 fatigue usage factors for nickel alloys in air. 16 MR. BANERJEE: So temperature has almost 17 no effect here. 18 MR. CHOPRA: For carbon and low-alloy l9 steels there is some effect. Going from room 20 temperature to 300 may reduce life by about 50 21 percent, but stainless up to 400. There's not much 22 effect. 23 MR. BANERJEE: Including nickel alloys? 24 MR. CHOPRA: Nickel alloys, no. At 400,

• 25 in fact, they show longer life.

NEAL R. GROSS But again, the data COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

36 1 is very limited. There's few data sets at 400 which 2 actually show longer life for alloy 600. But again, 3 at present, since all curves are based on room 4 temperature data, we are not taking any temperature 5 dependence for air. But for water effects, 6 temperature is important and explicitly defined in the 7 expressions to calculate fatigue life in water. 8 DR. WALLIS: That means it is through the 9 median of the data in some way? 10 MR. CHOPRA: I'll show you how we got the 11 best fit curves. 12 DR. WALLIS: It's supposed to be an 13 average right through the middle of the data. 14 MR. CHOPRA: Right. 15 DR. WALLIS: It's not best fit to a 95 16 percentile or something like that? You' 11 get to that 17 too, but what you're showing here is 18 MR. CHOPRA: Average, right. These 19 results show nickel alloy data for alloy 600 and some 20 of the welds. In BWR, normal water chemistry, BWR 21 environment and PWR environment and again, what we see 22 is the effects are similar to what we get for 23 austenitic stainless steels. There's larger effect in 24 low oxygen than in high oxygen. PWR environment has

• 25 larger effect than BWR, but the focal effect is much NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

37 1 less than what you would see for austenitic stainless 2 steel. 3 Typically, under certain conditions in 4 austenitic stainless steel we see a reduction of a 5 factor of 14 or 15. In this, the maximum is a factor 6 of 3. So the effect is much less, but we can use this 7 limited data to define the important parameters and 8 how to estimate environmental effects. 9 Now we have all this data. How do we 10 generate the expressions? All -- in air, all data, 11 fatigue data I expressed by this modified Langer 12 equation where fatigue life is expressed in terms of 13 strain amplitude and these constants A, B, C 14 DR. WALLIS: Is this an equation because 15 you plotted the data on log paper, is that why it is? 16 MR. CHOPRA: This is the expression used 17 and it presents the data best. 18 DR. WALLIS: It's because you plotted it 19 on log paper. It looks good on log paper and it's 20 linear. 21 MR. CHOPRA: Well, the trend is also-- it 22 does represent the trend. 23 DR. WALLIS: Okay. 24 MR. CHOPRA: And C is the fatigue limit or

• 25 related with the fatigue limit of the material.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. B is (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

38 1 the slope of that curve.* A'is a constant which would vary with heat to heat. Depending on a more resistant 3 material would give a higher A or lower means it's 4 less resistant to fatigue damage. 5 We can do a best fit of the data and also 6 use this A to represent heat to heat variability and 7 come up with a median value, how median material would 8 behave. Best fit gives me the average behavior, 9 whereas a distribution would give me how various 10 materials behave and I get a median curve and then 11 come up with a number which would bound 95 percent of 12 the materials. And that's what I'm going to show. 13 One more thing, another term, D can be 14 added to impute in 1, which would include parameters 15 like temperature, strain rate and so on. 16 DR. WALLIS: Does the ASME curve have a 17 similar equation? 18 MR. CHOPRA: Yes. The Langer equation is 19 very -- yes. 20 This shows for low-alloy steels in air and 21 water various heats. Now each did define even if I 22 have 10 data points, it's 1 point. Another may have 23 500 data points. But if it's the same material, it's 24 just one point on this plot. This way, I can give

• 25 you, we can determine the NEAL R. GROSS median COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

value for the (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

39 1 materials and if I select. a** fifth percentile number, 2 in this case, 5.56, if I select the A or 5.56, that 3 curve would bound 95 percent of the -- 4 DR. WALLIS: It's the coefficient. 5 MR. CHOPRA: So this is how we obtain the 6 design curve by defining what subfactors I need to 7 adjust the best fit curve for average curve to come up 8 with a design curve which would bound 95 percent of 9 the materials. 10 I'll give the loca probability of track 11 initiation. 12 MR. BANERJEE: There's B and C as well, 13 right? 14 MR. CHOPRA: B and C, what I do is use it 15 for normalizing to get A for each heat which is the 16 average heat and I get a standard deviation. That's 17 what I've plotted here. For the particular heat, I've 18 given the average value and the standard deviation for 19 the data set. 20 MR. BANERJEE: You lost me. 21 CHAIRMAN ARMIJO: B and C are relatively 22 constant. 23 MR. CHOPRA: A is the one that changes. 24 MR. BANERJEE: So you fix B and C to some

• 25 value?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

40 1 MR. CHOPRA: .Right, right. And we know 2 even environment does not change . The strain 3 threshold was close to fatigue limit so I don't have 4 to change the fatigue limit. And there is no data 5 which suggests that C changes, means that the fatigue 6 limit changes for material. 7 DR. WALLIS: The range of that is not very 8 big, but if N is E to the A, so it's a factor of about 9 10 on the whole range. 10 MR. CHOPRA: Right. 11 MR. BANERJEE: Do B and C govern the shape 12 of the curve? 13 MR. CHOPRA: Yes. Right. The slope is B. 14 C is where at 10 6 or 10 7

• 15 DR. WALLIS: I see where it's flat.

16 CHAIRMAN ARMIJO: So all the environmental 17 effects are just put into the A constant? 18 MR. CHOPRA: Right. 19 CHAIRMAN ARMIJO: Okay. 20 MR. CHOPRA: Now we come up with these 21 expressions which can be used for predicting fatigue 22 life under various conditions. Again, Langer equation 23 A, constant A; slope B and C. And this is the 24 environmental term B which would have these -- which

• 25 would depend on these three parameters for carbon low-NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

41 1 alloy steel, same for content, given by these 2 expressions, temperature, dissolved oxygen and strain 3 rate. 4 CHAIRMAN ARMIJO: Now the A is the five 5 percent number? 6 MR. CHOPRA: No. These are still the 7 average numbers. 8 CHAIRMAN ARMIJO: These are average 9 numbers. 10 MR. CHOPRA: Next, I'll get to where we 11 apply those adjustment factors to get the design 12 growth. 13 DR. WALLIS: What does N mean here? 14 MR. CHOPRA: Cycles -- 15 DR. WALLIS: Environment. N for 16 environment, is that PWR? 17 MR. CHOPRA: No, this is in error what the 18 expression is. This is in the light water reactor. 19 DR. WALLIS: Okay. 20 MR. CHOPRA: It doesn't matter whether 21 it' s BWR or PWR because these are the parameters which 22 will change in various environments, reactor 23 environments. 24 MR. BANERJEE: Is there no effective

• 25 hydrogen on it at all?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

42 1 MR. CHOPRA: In BWR environment, there's 2 about 2 ppm dissolved hydrogen, but I think it's the 3 hydrogen which is created by the austenitic reaction 4 which is more important than what is it does 5 control ECP, the electrical potential of the 6 environment. So hydrogen would change the ECP, but 7 below -250 electrical potential, effects are not that 8 much different. But you know, in crack growth rates 9 there is some effect, depending on -- well, in this 10 case all we use only 2 PPM hydrogen. 11 MR. BANERJEE: These are all done in 12 autoclaves or whatever? 13 MR. CHOPRA: And we do simulate these 14 conditions. BWR, it's high oxygen, high purity, very 15 high purity. And pressurized water reactor, again 16 high purity. Then we had boron or boric acid to get 17 boron, 1,000 PPM and 2 PPM lithium, by adding lithium 18 hydroxide. And measure the pH. We measure the 19 conductivity and maintain all these water chemistry 20 parameters constant during the test. 21 CHAIRMAN ARMIJO: These are flowing a loop 22 type -- 23 MR. CHOPRA: Very small flow rates. I 24 think if you look at the -- my plot, they would amount

• 25 to lo-s meter per second. Very low.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

43 1 CHAIRMAN ARMIJO: They're not static 2 autoclaves? 3 MR. CHOPRA: They're not static and they 4 are continuously reconditioned. So if they are, it's 5 once through. They're not repeated. 6 DR. WALLIS: How long are the tests done 7 typically? 8 MR. CHOPRA: Depends on the conditions. 9 At low strain amplitudes and low strain rates, it may 10 take up to 5 to 8 months and those results are very 11 limited. In the range which people have -- we have 12 tested .25 to .4 strain amplifies, it can take 13 anywhere from a few days to a month or two, depending 14 on the environmental effects. In air, they're much 15 longer. So one has to consider all of these. We 16 can't just dedicate and that's why you see very low, 17 less data under conditions which have very long 18 durations. 19 Now I just want to mention that these 20 expressions are average behavior after median 21 material. Same thing for rod and gas stainless steel. 22 Now as you mentioned that the slope of the 360 NG was 23 different, what we have done is we have used a single 24 expression to represent all grades of steel and this

• 25 number, the fatigue limit we chose what studies in NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

44 1 Japan have established. And Jaske and O'Donnell in 2 1978 pointed this out that the current design curve 3 for stainless steel was not consistent with the 4 experimental data. 5 DR. WALLIS: I want to check this about 6 oxygen. You say it's worse to have less oxygen? 7 MR. CHOPRA: Pardon me? 8 DR. WALLIS: N goes down when you have 9 less oxygen? 10 MR. CHOPRA: In stainless steel, life goes 11 down dissolved oxygen is low. 12 DR. WALLIS: But these it goes the other 13 way? 14 MR. CHOPRA: No. The oxygen, there's a 15 constant factor 16 DR. WALLIS: In the one before, the carbon 17 and low-alloy steels? 18 MR. CHOPRA: Yes. Now in carbon and low-19 alloy steel it's the high oxygen which is more 20 damaging. 21 DR. WALLIS: Then it doesn't make -- okay, 22 okay. That's right. Okay. Because I thought it was 23 the other way around. That's a negative -- 24 MR. CHOPRA: The strain rate term is a

• 25 negative.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

45 1 DR. WALLIS: That's right. I was crawling 2 through that and then I was trying to go back to 3 before. 4 MR. CHOPRA: Actually, this whole term is 5 6 DR. WALLIS: I understand that. Just 7 before, but the other with the stainless steel, the 8 low oxygen is bad. 9 MR. CHOPRA: Right. 10 DR. WALLIS: Okay, that's what I'm trying 11 to -- 12 MR. CHOPRA: I just mentioned that we 13 established a single curve and this we selected from 14 what was proposed by these studies.

 ~5                Now we have the specimen data.              We know 16 how to predict what will happen with specimens.

17 DR. WALLIS: What effect does this have on 18 welds of dissimilar metals? 19 MR. CHOPRA: Welds have different -- 20 DR. WALLIS: All together different? 21 MR. CHOPRA: Yes. 22 DR. WALLIS: Is there some basis for that? 23 MR. CHOPRA: It depends on the data. 24 DR. WALLIS: You're not addressing that?

• 25 MR. CHOPRA: No.

NEAL R. GROSS This is the current code COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202} 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

46 1 design curves for these grades or types of structural 2 steel. 3 CHAIRMAN ARMIJO: For example, a welded 4 stainless steel is like a cast stainless steel, a weld 5 6 MR. CHOPRA: I think the behavior is very 7 similar. But -- 8 CHAIRMAN ARMIJO: If it's similar, there's 9 a difference. 10 MR. CHOPRA: Because in some cases there 11 may be difference. We are just looking at here the 12 rod products. 13 CHAIRMAN ARMIJO: Stainless. 14 DR. WALLIS: Is there any effect of 15 fluence on this? 16 MR. CHOPRA: Irradiation? I'm sorry, I 17 didn't get that? 18 DR. WALLIS: Is there any effect of 19 fluence? 20 MR. CHOPRA: We're not studying that. 21 There is an effect, but that's not -- in the design 22 curve 23 DR. WALLIS: It's all synergistic. 24 MR. CHOPRA: No environment is considered

• 25 and the designer has to account for other environments NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

47 1 which are not considered in their design. 2 We have the data for specimens. Now to 3 use it to come up with a design curve for components,

  *4 I mention that they apply this adjustment factor of 20 5 on life and this            factor      is made up of effects of 6 material availability,              data scatter,         size,    surface 7 finish,        loading history.

8 In the current code, these are the 9 subfactors which are defined in the basis document. 10 Loading history was not considered, a total of 20 11 adjustment factors. In our study, based on the 12 distribution I showed for individual materials, this 13 subfactor can vary anywhere from a minimum of 2.1 to 14 2.8. These numbers are taken from studies J.n the 15 literature. Size can have an effect, minimum 1.2, 1.4 16 and so on. So we see a minimum of 6, maximum of 27. 17 When we take a large number, for example, 20, what we 18 are basically saying is I have a very bad material 19 which is very poor in fatigue resistance. I have 20 rough surfaces and I have the worse loading history. 21 So we used a Monte Carlo simulation and 22 using these as a log normal distribution to simulate 23 what would be the best adjustment needed to define the 24 behavior of components .

• 25 CHAIRMAN ARMIJO:

NEAL R. GROSS So the present study, COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

48 1 you've agglomerated the date for carbon steels and 2 austenitic stainless steels and all these factors are 3 all pushed together. 4 MR. CHOPRA: Right. 5 CHAIRMAN ARMIJO: But you've separated 6 them. Are they different? 7 MR. CHOPRA: No, these are not the effects 8 of materialability is here and that depends on the 9 material. But effects of surface finish of the 10 component, size of the component or loading history 11 means random loading, high stress cycle followed by 12 low stress cycles. These in the current data, 13 these effects are not included. So somehow I need to 14 include these effects to come up with a design curve 15 which would be applicable to a real actual reactor 16 component. 17 Now the question is 20 was selected with 18 some basis. Is this reasonable because quite often, 19 this is what is being questioned. There may be 20 conservatism in this which we need to eliminate. So 21 we are trying to see what possible conservatism might 22 be there in this margin or the adjustment factor of 23 20. 24 DR. BONACA: Twenty was arbitrarily taken

• 25 as a bounding number, right?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

49 1 Where did you get the 27? 2 MR. CHOPRA: I just took from the 3 literature what people have observed, effect of 4 surface -- surface finish is very well documented. 5 Depending on the average surface finish, an autonomous 6 value of surface finish, they have a harmless 7 reduction in light. So I can use typical finish for 8 grinding or milling operation and so on. It's well 9 documented. We can come up with what would be a 10 typical fabrication process, minimum and maximum. So 11 that's how we came up with this number. 12 DR. WALLIS: What is the basis of the 13 numbers? Is it trying to bound the data or bound the 14 95th percentile? 15 MR. CHOPRA: To come up with a design 16 curve which will be applicable to components. 17 DR. WALLIS: What's the basis of this? Is 18 there a rationale? 19 MR. CHOPRA: Right, 95 percent. 20 DR. WALLIS: Ninety-five, 99, 95? 21 MR. CHOPRA: Ninety-five? 22 DR. WALLIS: Why is 95 good enough? 23 MR. CHOPRA: Well -- 24 DR. WALLIS: Why not 99?

• 25 MR. CHOPRA: We NEAL R. GROSS can COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

do a statistical (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

50 1 analysis to see what are the probabilities. 2 CHAIRMAN ARMIJO: I think 95/5 basis is 3 sort of a typical basis we've used in a lot of other 4 studies on failure data. But the reason that 95/5 is 5 okay is we've already done risk studies with fatigue 6 cracks initiating and growing to failure and growing 7 to leakage and the fact of a 95/5 probability of 8 fatigue crack initiation still keeps you in acceptably 9 low probability of getting a failure. 10 DR. WALLIS: Okay, so it's related to the 11 overall -- 12 CHAIRMAN ARMIJO: Overall margin, yes. If 13 it were just a 95/5 to failure it would be an 14 unacceptable criteria. 15 DR. WALLIS: If the consequence were much 16 worse, you'd need to have a -- 17 CHAIRMAN ARMIJO: Yes. 18 MR. BANERJEE: Can you expand a bit more 19 by what you mean by this log normal distribution? 20 MR. CHOPRA: We assumed that the effects 21 of all of these parameters have a log normal. 22 MR. BANERJEE: Of some mean? 23 MR. CHOPRA: Right. And I took these two 24 ranges as the 5th and 95th percentile of that

• 25 distribution.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. {202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

51 1 MR. BANERJEE:** So what happens if you 2 chose a different distribution? Does it make any 3 difference to the results? 4 MR. CHOPRA: We have tried three 5 different, I think Bill tried and this gets the best - 6 7 MR. BANERJEE: Best in what sense? 8 MR. CHOPRA: Very consistent result. 9 There's not much difference between normal and log 10 normal was not much difference. And log normal -- you 11 want to -- 12 DR. SHACK: It's basically sort of an 13 arbitrary engineering judgment question. Experience 14 has indicated that when we have enough data, these 15 things do seem to be distributed log normally. 16 We generally don't have enough data, 17 actually, to determine the distribution. So we have 18 sort of just made the engineering judgment that the 19 log normal is close enough. 20 As John was explaining 21 MR. BANERJEE: It doesn't affect the 22 results. 23 DR. SHACK: It doesn't affect the results 24 very much. What we're trying to do is to bound the

• 25 data in some reasonable NEAL R. GROSS fashion COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

because the (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

52 1 consequence is not core damage when we're done. The 2 fact that we're not highly precise on this is not 3 something that concerns us, but we think we've built 4 in sufficient conservatism to account for these 5 variables in a sensible way without going overboard. 6 And the fact that these affects can be 7 considered as independent is also something we don't 8 have data on. We have to sort of work on an 9 engineering judgment basis. So the Monte Carlo 10 simulation that we do assumes the log normal 11 distribution, assumes the independence. 12 MR. CHOPRA: I want to add one more, quite 13 often, actually in the welding research that WRC 14 Bulletin by industry, they are suggesting that in this 15 margin of 2 0, we can use a factor of 3 to offset 16 environment. This kind of analysis can suggest or 17 show that 3 number is very high. We do not have that, 18 at least what is the possible -- 19 DR. KRESS: Is it a theoretical basis for 20 assuming the log normal? There may be, you know. You 21 can look at the physical phenomena and -- 22 DR. SHACK: Well, the loading, probably 23 DR. KRESS: Loading you would think would 24 be log normal. I'm not sure about the effects of the

• 25 other things.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

53 1 DR. SHACK: ...The log normal turns out to be 2 slightly more conservative than the normal and so 3 those were my-- if I don't have enough data to define 4 a distribution -- 5 DR. KRESS: You might as well use -- 6 DR. SHACK: I pick one or the other, sort 7 of on some sort of engineering judgment. The 8 differences are not very large between the two and we 9 just pick the log normal. 10 DR. WALLIS: If you know the distribution, 11 why do you need -- if you know the equation for the 12 distribution, why do you have to do a Monte Carlo 13 analysis? 14 DR. SHACK: Because I'm taking a bunch of 15 random variables. 16 DR. KRESS: That's the way you find the 17 mean, right? 18 MR. CHOPRA: There are four or five of 19 these things. 20 DR. SHACK: There are four or five 21 distributed variables. 22 DR. WALLIS: Easier to do it than to try 23 to go through the mathematics of predicting. 24 DR. SHACK: Yes, it's easier. Yes, I

• 25 could do it the other way, right.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005*3701 www.nealrgross.com

54 1 DR. KRESS: Is the 95 value four times the 2 mean? 3 DR. SHACK: No. 4 DR. KRESS: It has to be if it's log 5 normal. 6 DR. WALLIS: Four times the mean on a 7 constant A would be horrendous. 8 DR. KRESS: You've got to find the mean 9 value. 10 DR. WALLIS: Mean value is about five. 11 CHAIRMAN ARMIJO: Let's move on. 12 MR. CHOPRA: Doing this simulation, we get 13 these curves where this dash curve is now for the 14 specimen, the distribution of A for the specimen and 15 solid would be the distribution for the real 16 component. And we see that the median value has 17 shifted by about 5.3. 18 And 95 of 5th percentile is a factor of 19 12. So we can say that in this factor of 20, there is 20 some conservatism and we can use adjustment factor of 21 12 on life instead of 20. 22 DR. WALLIS: Where did 20 come from? 23 MR. CHOPRA: It's in the design basis 24 document of the current code .

• 25 DR. WALLIS: It's the judgment of a few NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

{202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

55 1 wise men? 2 CHAIRMAN ARMIJO: Many years ago . 3 MR. CHOPRA: Basically, that's what it 4 was. 5 MR. BANERJEE: Not so bad. 6 MR. CHOPRA: The design has several -- 7 yes. 8 I've covered -- there is some conservatism in the 9 fatigue evaluations and often this conservatism is IO used to offset environmental effects and there are two 11 sources of conservatism, in the procedures themselves, 12 the way we define design stresses and design cycles or 13 this adjustment factors of 2 and 20 . 14 I showed there's not much margin, only 1. 7 15 in this factor of 20, but the current code procedures 16 17 DR. WALLIS: Is there enough to account 18 for environmental effects? 19 MR. CHOPRA: No, environmental effects can 20 be as high as a factor of 15. 21 DR. WALLIS: Yes. 22 MR. CHOPRA: Or carbon C would be even 23 higher. 24 DR. WALLIS: These are all reactor data

• 25 you've got, right?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

56 1 MR. CHOPRA: Those are unless you 2 define the operating transient conditions. In certain 3 conditions those may be possible, but again, it's up 4 to the designer to define what are the conditions 5 during a transient, mean strain rates, temperatures 6 and so forth. 7 MR. BANERJEE: But I'm wondering whether 8 in your database you have anything which you've 9 evaluated from N reactor data or reactor data. Do you 10 have any information at all? 11 MR. CHOPRA: There are some components and 12 so on and I list a few examples where there have been 13 some studies. And I '11 show you near the end of this . 14 DR. SHACK: The trouble with doing this 15 with field data is it's hard to control variables like 16 knowing that the strain range and because that has 17 such a strong effect on it. Unless you know that 18 accurate, it's hard to back out the result. 19 MR. CULLEN: Bill Cullen, Office of 20 Research. I'd like to explore Dr. Banerjee's question 21 a little more to find out what's behind it. 22 Are you concerned about irradiation 23 effects which really do not come into play for 24 pressure boundary? Or are you concerned about the

• 25 actual aqueous environment and its characteristics?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

57 1 I'm not sure -- what is the basis? 2 MR. BANERJEE: Well, the basis is more -- it would be nice to see some validation under field 4 conditions. There are always sort of surprises 5 between the lab and what happens in the field and even 6 if this sort of validation is not all that thorough, 7 a couple of data points would set your mind at rest 8 that it's not some unexpected factor that comes in. 9 It's more like-- I have a concern always 10 of going from the lab to a real field situation. It's 11 not for any specific issue, not like radiation or 12 combination of factors or boron plus temperature in 13 fatigue cycles which are slow. All these things may 14 or may not be there but just a general question, more 15 a general question. 16 MR. CULLEN: I understand the general 17 question. I'm a little concerned about your word 18 about there always are surprises when you go from the 19 laboratory to the actuality. 20 MR. CHOPRA: Maybe that's too strong. 21 MR. CULLEN: A little bit. 22 (Laughter.) 23 DR. WALLIS: Oftentimes, surprises may be 24 small .

• 25 MR. CULLEN: Thank you.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

58 1 MR. BANERJEE: . I don' t mean to say that 2 this stuff should not be used or anything. Right. 3 MR. CHOPRA: I mentioned that in fatigue 4 evaluations the procedures are quite conservative, but 5 the code allows us to use improved approaches, for 6 example, finite element analysis, fatigue monitoring 7 to define the design stresses and cycles more 8 accurately. So most of this conservatism can be 9 removed with better methods for defining these design 10 conditions. 11 So in that case, there is a need to 12 address the effect of environment explicitly in these 13 procedures . 14 Now the two approaches which we can use 15 either come up with new set of design curves or use 16 some kind of correction factor, Fen* Now since 17 environmental effects depend on a whole lot of 18 parameters, temperature, strain rate and so on, either 19 we come up with several sets of design curves to cover 20 the possible conditions which occur in the reactor or 21 field conditions or if you use a bounding curve, it 22 would be very conservative for most of the conditions. 23 Whereas this correction factor, 24 approach is relatively simple. You can-- it's very

• 25 flexible. You can calculate the environmental effects NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

59 1 for a specific condition. And this is what is being 2 proposed in this reg. guide. 3 The correction factor is nothing, and this 4 was proposed in 1991 by the Japanese. A correction 5 factor is nothing but a ratio of fatigue life and air 6 versus life and water. So we have these expressions 7 I showed you in the previous slides and we can then

  .8 calculate       Fen for different steels, carbon steel, low-9 alloy steel, and below a strain threshold there's no 10  environmental effects, so the correction factor would 11  be one.

12 Other than that, we use these expressions, 13 actual conditions, temperature, strain rates and so on 14 to calculate the correction factor. To incorporate 15 environmental effects, we take the usage, partial 16 usage factors obtain for specific transients in air, 17 U1, U2 and so on, multiplied by the corresponding 18 correction factor and we get usage factor in the 19 environment. 20 Now to calculate usage factors in air, we 21 should use design curves which are consistent with or 22 conservative with respect to the existing data. And 23 as has been pointed out quite a few years back, the 24 current code curve for stainless steel is not

• 25 consistent with the current existing data and should NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

60 1 not be used for obtaining usage. And I just want to 2 show before I get to that, these are the expressions

  .3 for nickel allows.           Correction factor,           again,      as a 4 function of these three variables.                  And usage and air 5 would       be obtained     from    the     curve     for  austenitic 6 stainless steels.

7 Now I mentioned that the current design 8 curve for austenitic stainless steel is not consistent 9 with the data. I plotted the fatigue data for 316, 10 304 stainless in air, different temperatures and this 11 dashed curve is the curve, current code mean curve. 12 This is the mean curve which was used to obtain the 13 design curve. 14 DR. WALLIS: Where is your design curve? 15 MR. CHOPRA: Design curve would be what 16 you adjust this curve for mean curve correction. 17 DR. WALLIS: Your recommended curve would 18 actually bound the data, wouldn't it? 19 MR. CHOPRA: This is the best actually, 20 this data, the curve is based on austenitic stainless 21 steel. 22 DR. WALLIS: I thought you were 23 recommending a bounding curve with this factor. 24 MR. CHOPRA: I'm just trying to show that

• 25 the current NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

{202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

61 1 DR. WALLIS: What's your design curve? 2 You should show that, shouldn't you? 3 MR. CHOPRA: These are mean curves. 4 DR. SHACK: This is air data, mean curve. 5 If we put a design curve on here, we could have a 6 design curve in air and a design curve in -- 7 DR. WALLIS: There's all this air data.

  *8 Are you going to get to your -- it's so far down the 9 road, I can't          okay.

10 CHAIRMAN ARMIJO: I think he' s just trying 11 to show the difference between the two sets of means. 12 MR. CHOPRA: That the current means -- 13 DR. WALLIS: You do show the effect of the 14 F factors yet. 15 MR. CHOPRA: No. I'm just trying to show 16 17 DR. WALLIS: We've just been talking about 18 19 DR. SHACK: What he's trying to 20 demonstrate here is that the F factor requires him to 21 take the ratio in air. He's got to have the right air 22 curve. 23 MR. CHOPRA: And the current mean curve 24 for air, for austenitic stainless steel, is not

• 25 consistent with the data.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

62 1 Now I'd like to mention one thing, it's 2 been suggested that this curve, the data may be

  '3 different       from   the mean curve because               of   the way 4 fatigue life has been defined or the way we conduct 5 experiments.        I can assure you that this difference in 6 the mean curve and the data is not due to any artifact 7 of test procedures or the way the fatigue life is 8 defined in terms of failure or 25 percent load drop.

9 DR. WALLIS: What occurs to me is the ASME 10 code mean curve was a mean curve to something. 11 MR. CHOPRA: Right. 12 DR. WALLIS: And it was presumably through 13 other data . 14 MR. CHOPRA: This curve, the current code 15 curve was based on very limited data. Now we have 16 much more. So I'm just showing that the data which 17 has been obtained since then is not consistent with 18 what we have. 19 DR. WALLIS: You have a much broader data 20 base. 21 MR. CHOPRA: Right. 22 DR. WALLIS: Okay, that's why yours is 23 better? 24 (Laughter.}

• 25 MR. CHOPRA: We NEAL R. GROSS are COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

saying we should (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

63 1 change the current code curve. The current code curve 2 is not consistent with 3 DR. WALLIS: It must have been based on 4 something. 5 MR. CHOPRA: And that data is somewhere in 6 here, up here . But since then we have much more data. 7 DR. WALLIS: Either that or steels have 8 been getting weaker. 9 MR. CHOPRA: Actually, that is the reason. 10 Mostly like because of the strength of the steel, 11 probably these curves were obtained on steel which was 12 stronger. 13 DR. WALLIS: Wait a minute -- 14 MR. CHOPRA: Possible difference. 15 MR. CULLEN: Bill Cullen, Office of 16 Research again. Omesh, if you could go back to that, 17 I'd like to also point out that the curves on which 18 the original ASME code were based I think the data 19 only went out to a factor of about, fatigue life of 20 10 6 or something. 21 MR. CHOPRA: Not even 6. 22 MR. CULLEN: So you've got two orders of 23 magnitude extrapolation there that we're doing now to 24 illustrate. But the other thing again is those tests

• 25 were all done at room temperature and you're showing NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

64 1 data from a wide variety of temperatures up to and 2 including operational. 3 MR. CHOPRA: Stainless does not -- 4 MR. CULLEN: Doesn't show much difference, 5 right. To me, that's kind of the point. It all hangs 6 together on the lower curve. 7 MR. CHOPRA: This difference is genuine. 8 We need to use a different curve. And we have now 9 proposed a design curve for air for austenitic 10 stainless steels, the solid line. The current dashed 11 line is the current code of 10 6 and the high cycle 12 extension in the code. And the solid line curve is 13 based on the Argonne model plus adjustment factors of 14 12 on life and 2 on stress. It's not 20 and 2. It's 15 12 and 2. 16 DR. WALLIS: Now the kink that you have 17 here at 10 6 doesn't appear in the previous curve you 18 showed. 19 MR. CHOPRA: The design curve extends only 20 up to 10 6

• 21 DR. WALLIS: So you've just extrapolated 22 it here in your figure?

23 MR. CHOPRA: Yes, because now there is a 24 need to go all the way to lOu .

• 25 DR. WALLIS: But you're saying mean curve, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

65 1 so where do you stop at 10 6 ?* 2 CHAIRMAN ARMIJO: Two different things 3 here, hold on. 4 MR. FERRER: This is John Ferrer. I think 5 originally the stainless steel curve went out to 10 6

• 6 Later, they got more data at high cycles and the data 7 was clearly showing that there was a drop off and so 8 they -- this is an artifact of fairing the two curves 9 together and the new correction we're doing really is 10 straightening out what they should have straightened 11 out to begin with.

12 DR. WALLIS: Well, it's a curve, it can't 13 be straightened out . 14 (Laughter.) 15 MR. FERRER: Fur the earlier slide was the 16 man curve through the data. Now we are talking about 17 the code curve which would include these factors. 18 DR. WALLIS: Okay. 19 MR. GURDAL: There is still a curve A, B 20 and C. 21 My name is Robert Gurdal. I'm AREVA, 22 Lynchburg, Virginia. Those curves is because before 23 just now there are three curves, there is A, B and C 24 and they are not indicated there. I just wanted to be

• 25 sure everybody knows.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I I I 66 1 The reason you have the lower one which is 2 called a curve C -- 3 MR. CHOPRA: But the region which we are 4 talking about is this 10 6 to 10 5 MR. GURDAL: You go above 10 6 , you have a 6 curve A, curve B and curve C. 7 MR. CHOPRA: I have plotted that. 8 MR. GURDAL: The correct curve is curve A 9 which is the top one. 10 DR. WALLIS: So it's C on this figure and 11 it's A on the previous figure. 12 MR. GURDAL: Maybe, it could be. 13 DR. WALLIS: Maybe. It probably doesn't 14 matter that much. 15 MR. GURDAL: And the C is for the heat 16 affected zone compared to the A. 17 DR. WALLIS: This is the A in this one. 18 MR. GURDAL: That one could be the A, 19 because it does not have the kink. 20 MR. CHOPRA: This is the mean curve. 21 MR. GURDAL: Oh, that's the mean curve. 22 Sorry about that. But the design curve, if you go to 23 the design, there is a curve continuing without any 24 disconnection .

• 25 DR. WALLIS: Without any king, yes.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. Okay. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I, 67 1 MR. GURDAL:. :And .. that's the A. This one 2 is a C . 3 MR. CHOPRA: But the region we are talking 4 about is this. 5 MR. GURDAL: Okay, but the question was

  *6    about 10 6

• 7 MR. CHOPRA: Which needs to be corrected.

8 DR. WALLIS: Okay, we've resolved that, I 9 think. Thank you. That's very good. 10 CHAIRMAN ARMIJO: Which gets to the point, 11 your design curve treats the weld heat affected zones 12 or the base rna terial, everything as the same as 13 opposed to the code . 14 MR. CHOPRA: Yes, I think so. 15 MR. FERRER: I think so. In the code, I 16 think the previous gentleman was talking about their - 17 - in the high cycle regime, there are three separate 18 curves proposed by ASME that extend past the 10 6 19 cycles. 20 In our proposal we've just bounded that 21 with one curve. 22 MR. CHOPRA: We also have generated design 23 curves for carbon and low-alloy steels based on the 24 same approach using the Argonne models and adjustment

• 25 factors of 12 and 2. This is for carbon steel and NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

i. 68 1 next is for low alloy. 2 Now current code curve for these is only 3 10 6 and now this is the current code curve and an 4 extension has been proposed by a subgroup, fatigue 5 strength. This was proposed a few years back and it's 6 still not approved by the ASME code committees. We 7 are -- we have another approach to define extension of 8 this curve beyond 10 6 cycle. I just wanted to give a 9 couple of slides to show that. 10 What the subgroup fatigue strength 11 proposed was extension of the curve which is based on 12 load control data and the data extends only up to 10 6 13 and they use maximum effect of mean stress and they 14 propose extension which is expressed by applied stress 15 amplitude given in terms of life with an exponent of 16 -. 05 which means 5 percent decrease in life, in stress 17 every decade. And since the data only extends up to 18 5 times extrapolation to 10 11 may give 19 conservative estimates. 20 Another way of extending this curve would 21 be to use the approach with Manjoine had proposed a 22 few years back where the high-cycle fatigue is 23 represented by elastic strain with life blots and if 24 we use existing data which we have extending up to 10 8

• 25 cycles for these various speeds, we get a slope of -

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. {202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

69 1 007. Manjoine proposed - .*01 and we can use this 2 expression where the exponent is smaller and which is 3 consistent with the data and this would be for the 4 mean curve. 5 Now we take this adjusted for mean stress 6 correction using Goodman relation which is a 7 conservative approach and actually if we do that this 8 exponent would be .017. So it's slightly lower than 9 what is being proposed by the subgroup fatigue 10 strength, but we can use this expression and that's 11 what we have used to define that extension to the 12 curve. 13 DR . WALLIS: When you make these 14 proposals, did you negotiate something with ASME or 15 did you just say this is what we use -- 16 MR. CHOPRA: This has been presented to 17 them. 18 DR. WALLIS: There wasn't any give and 19 take. It was just -- you deduced this from your data? 20 MR. CHOPRA: I at tended the subgroup 21 fatigue strength and all our work has been presented 22 there. 23 DR. WALLIS: But the proposal is 24 essentially yours. It isn't some compromise proposal .

• 25 It's your proposal.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

II 70 1 MR. CHOPRA:_ This was proposed by Manjoine 2 a few years back, so this is nothing new. 3 DR. WALLIS: All these green curves are 4 Argonne curves, proposed by Argonne? 5 MR. CHOPRA: No, the best fit curves are 6 what we have defined. 7 DR. WALLIS: Right, so they're not 8 something which has been negotiated and agreed on or 9 anything like that? 10 CHAIRMAN ARMIJO: It's certainly been 11 discussed. 12 DR. WALLIS: It's been discussed. IT's 13 been presented. ASME hasn't come around and said yes, 14 you guys are right. 15 DR. SHACK: One thing to think about for 16 the carbon and low-alloy steels, there's really in air 17 there's no disagreement over the mean curve. The 18 shape may shift just a smidgen, but the only real 19 difference between this design curve and the current 20 is they use a factor of 12 instead of 20. Then you do 21 have the discussion over how to extend it. 22 The environmental effect is a -- 23 DR. WALLIS: It's the big one. 24 DR. SHACK: That's the big one.

• 25 CHAIRMAN ARMIJO:

NEAL R. GROSS In the reg. guide, does COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

71 1 this curve really extend out to 10 11 or does it -- is 2 it truncated at 10 7 , since there seem to be a big 3 difference. 4 MR. CHOPRA: The proposal is up to 10 11 *

  '5                   CHAIRMAN ARMIJO:          Up to 10 11 , but compared 6    to the ASME code for this particular steel, your curve 7    is nonconservative.

8 MR. CHOPRA: Well, this is 9 CHAIRMAN ARMIJO: You predict a much 10 longer life. 11 MR. CHOPRA: This is based on the data we 12 have. 13 CHAIRMAN ARMIJO: Right, but nobody has 14 data out to 10 11

• 15 MR. CHOPRA: No.

16 CHAIRMAN ARMIJO: It's a less conservative 17 18 DR. WALLIS: You have a C. You have a 19 constant C or -- 20 CHAIRMAN ARMIJO: Right. 21 DR. WALLIS: I'm surprised it isn't 22 completely flat to a green curve. 23 MR. CHOPRA: Made up of two. I mentioned 24 that extension is a different slope .

• :25 DR. WALLIS: Do they ever have 10 11 cycles NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

72 1 in a nuclear environment? 2 MR. FERRER: Vibration -- 3 DR. WALLIS: Shaking things that shake. 4 MR. CHOPRA: So the method to apply the 5 correction would be to use for carbon low-alloy steel 6 you can use either the current code design curves or 7 the curves I've mentioned to reduce some conservatism. 8 As you see, it's they' re based on

  .g adjustment factors of 12, rather than 20.

10 For austenitic stainless steels and nickel 11 alloys, we use a new design curve for austenitic 12 stainless steels. And in the appendix to NUREG, there 13 are certain examples given to determine some of the 14 parameters. 15 For example, lab data shows quite often 16 people don't know how to calculate, how to define the 17 strain rates. Lab data shows average strain rate 18 always is a conservative approach. 19 And similarly, if we have a well-defined 20 linear transient temperature change, that can be 21 represented by average temperature and it could be 22 okay. 23 Now this one shows two more slides and 24 I' 11 be done. There was a question that lab data does

• 25 not represent the feed. There are certain reports NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005*3701 www.nealrgross.com

73 1 where some operating reports where some operating 2 experience and component test results have been

 - *- ------3 .published.

4 This is EPRI report, 1997, and gives a

           *5  complete chapter, a couple of them, giving examples of 6  corrosion      fatigue    effects       on nuclear       power     plant 7  components.

8 Similarly, studies in Germany, MPA and 9 other places have shown the conditions which lead to 10 what they call strain-induced corrosion cracking. 11 This was demonstrated for BWR environments. And there 12 are examples, even these examples are component test 13 results. We support the lab data . 14 I want to just show the results of one 15 particular test, component test, recent tests, again, 16 sponsored by EPRI where they used tube u-bend tests 17 tested in PWR water at 240. And I'm just plotting the 18 results for a given strain amplitude what was the 19 fatigue life they measured. 20 In earth environment, these are the 21 triangles. So that serves as a baseline you would 22 expect in air. Then they tested in PWR water in two 23 conditions: a strain rate of .01 percent per second 24 and diamonds are .005 percent per second. And this

• 25 would give me for this strain amplitude a life in air NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

{202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

74 1 of 12,500. This is about 36,000. This is 1700. And 2 you can determine for a component test what is the 3 environmental factor. 4 In this test, inert environment cracks 5 were on the OD. And they were biaxial conditions. 6 And the water, they were on the ID. And nearly 7 uniaxial. So since there was a conversion, there's a 8 question whether this number is accurate. 9 There's another way we can determine the 10 baseline life. They have a very well-defined strain 11 rate effect between these two. I applauded the 12 component test results with the lab data, exactly the 13 same slope and we know somewhere there's a threshold . 14 That would be the life in air. So I've got a number 15 8,000; 12,000. I use an average of 10. Gives me a 16 reduction of 5.8 for one strain rate; 2.8. 17 And the Fen we have presented, give you 18 5. 5 and 3. 6. Ii think these are very reasonable 19 comparisons from a real component test. 20 MR. BANERJEE: So the test was

• done 21 outside the reactor, right?

22 MR. CHOPRA: This is a component test, 23 where they took an actual u-bend tube and strained it. 24 So it's not a small specimen. They are testing a real

• 25 component it demonstrates NEAL R. GROSS that COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

lab data is {202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

75 1 applicable to actual component test conditions. 2 CHAIRMAN ARMIJO: Did you compare any of 3 the other component tests that you referenced in the 4 previous slide with your data to see how your data 5 predicts? 6 MR. CHOPRA: Some of the earlier, no, we 7 have not. 8 MR. BANERJEE: Do you have any idea of the 9 is there anything which happened in a reactor where 10 you have the strain history or something for a period 11 of time? 12 MR. FERRER: I think the answer to that is 13 it's very difficult to have the exact data on the 14 strain history in an actual operating event. We've 15 tried to estimate it and the best you can do is 16 estimate it. I think Omesh presented some references. 17 I think the EPRI one which attributed some of the 18 cracking to environment, but you couldn't prove it 19 absolutely because you just don't have the exact 20 temperature measurements and the strain measurements 21 at the location of your cracks. 22 MR. BANERJEE: But you can estimate them, 23 right? Based on those estimates, what does it look 24 like? -* 25 MR. FERRER: If NEAL R. GROSS you COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. go back to the (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

76 1 reference EPRI report, you. know, I think based on 2 their estimates they attribute some of it to 3 environmental, but I say those estimates are very 4 crude. They're not nearly as controlled as the lab 5 data and if you look at fatigue, the -- at the low 6 cycle end, the small change in stress gives you a 7 fairly large change in the number of cycles if you

  .8 look at the shape of the curve.

9 And so it's not that easy. There are some 10 estimates, but they're more judgmental than accurate 11 calculations. 12 MR. BANERJEE: But the evidence or 13 supports -- what you're saying -- 14 MR. FERRER: Well, there's some evidence. 15 What you'll hear from -- probably from ASME is the 16 overall operating experience doesn't show that there's 17 a big problem there. 18 MR. BANERJEE: Okay. 19 CHAIRMAN ARMIJO: Okay. That's it? 20 MR. CHOPRA: Yes. 21 CHAIRMAN ARMIJO: Any other questions from 22 the Committee? 23 MR. GONZALEZ: I would like to go back to 24 the reg. guide to present a summary of the three

• 25 regulatory positions.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

77 1 Regulation posit'ion 1, we are endorsing 2 that we will calculate fatigue using air with ASME 3 code analysis procedures plus use the ASME code air 4 curves for new ANL modern air curves. This is for 5 carbon and alloy steels only. 6 Then we will calculate the F~ using the 7 appendix A of the NUREG for carbon and alloy steels 8 and this will be applied to calculate the 9 environmental uses factor. 10 But we're given the option of using the 11 ASME curve or the new air curve from the ANL model. 12 Or austenitic stainless steel, we will calculate the 13 fatigue use factoring there with the ASME code 14 analysis procedure, plus the new ANL model air 15 stainless steel curve. 16 We 11 use the -- also the Fen equation for I 17 stainless steel and then calculate the environmental 18 usage factor. 19 For nickel chrome alloys, will be Alloy 20 600, 690. You will use again the ASME code analysis 21 procedure plus the new ANL model air stainless steel 22 curve. As the reason was it was explained before was 23 because of the new data. 24 And if the Fen specifically for nickel

• 25 alloys and calculate the NEAL R. GROSS usage COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

factor the (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

78 1 environmental fatigue usage factor. 2 In summary, Reg. Guide 1.207 will endorse 3 the use of a new air curve for austenitic stainless 4 steels and also will endorse the Fen methodology. It 5 will give guidance on incorporating the environmental 6 correction factor, the fatigue design analysis and

  .7 this is described in Appendix A of the NUREG report 8 and also the NUREG report will describe in detail the 9 technical basis.

10 That's it. Any more questions? 11 CHAIRMAN ARMIJO: Okay, any questions? 12 We're scheduled for a break about now, but we're a 13 little bit ahead of schedule. I don't know if we can 14 reconvene in 15 minutes or do we have to wait until 15 3:35? 16 We'll just take a 15-minute break. Be

 £7  back at 3:25.      Is that right?          3:25, thank you.

18 (Off the record.) 19 CHAIRMAN ARMIJO: Okay, we've got 20 incredibly we're about five minutes ahead of schedule, 21 so that's good. 22 So Mr. Gonzalez, would you like to 23 continue? 24 MR. GONZALEZ: This is our second part,

• 25 second presentation. It's in the resolution to public NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

79 1 comments. The Draft Guide 1144 and the Draft NUREG 2 CR-6909. 3 There were eight correspondents that 4 submitted a total of 56 comments, both the draft 5 Regulatory Guide and the draft NUREG and all comments 6 were addressed individually. 7 The final reg. guide 1.207 and the final 8 NUREG report reflects a resolution of these comments. 9 There were six main issues identified. 10 The next slide is an example of the table 11 that was provided to the ACRS where it's showing all 12 the comments, how it was individually -- there was an 13 individual response for each of them . 14 CHAIRMAN ARMIJO: Are these all the 15 comments? 16 MR. GONZALEZ : These are the six main 17 issues that we kind of -- 18 CHAIRMAN ARMIJO: Right, but -- 19 MR. GONZALEZ: Six main issues were 20 identified, but not all of them. The numbers in the 21 parentheses are the comments that apply to that 22 particular issue, so comments 1, 714, 16, 45, 521. 23 CHAIRMAN ARMIJO: I just noticed, you 24 received some comments, obviously from AREVA .

• 25 MR. GONZALEZ: Yes.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

80 1 CHAIRMAN ARMIJO:* . .You've received comments 2 from GE. 3 MR. GONZALEZ: Yes. 4 CHAIRMAN ARMIJO: You did not receive any 5 comments from Westinghouse?

  '6                MR. GONZALEZ:         We received Westinghouse.

7 CHAIRMAN ARMIJO: I didn't see any there. 8 MR. GONZALEZ: No. We've got GE, NEI, 9 ASME. 10 CHAIRMAN ARMIJO: Okay. All right, thank 11 you. 12 MR. GONZALEZ: Then we identified the six 13 issues and this is where I'm going to address each one 14 of them. 15 The first one is the -- has to do with l6 operating experience and the applicability of the 17 specimen data. The comment was that the -- the first 18 comment was there's no operating experience to support 19 the need for this conservative design rules. And our 20 response was that there was numerous samples on the 21 fatigue cracking of nuclear power plant components. 22 As an example, reported in the EPRI report reference 23 here. 24 The other issue that has to -- is about

• 25 the comments, questioning, NEAL R. GROSS the applicability of the COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

81 1 specimen data being representative of the actual 2 components and service. This being the applicability 3 of the lab data, the component behavior has been 4 demonstrated by mockup and component tests and 5 references were provided in the previous, Omesh' 6 presentation. In fact, it's the basis for that 7 current ASME code fatigue curves. 8 The second cormnents have to do, the second 9 set of cormnents have to do with the details on the 10 approach. One of the cormnents said that the reference 11 made to other guidance containing similar Fen 12 approach, like the Japan Fen equations are also 13 acceptable and endorsed . 14 Our response is that the papers listed in 15 NUREG CR-16909 are for reference only and Section C of 16 regulatory position of the regulatory guide contains 17 the methodology endorsed by the staff. 18 The second issue on the details on the 19 approach is that -- I'm quoting that "since draft 20 Guide 1145 utilizes a similar Fen methodology to that 21 evaluated in MRP-47 revision 1, the issues identified 22 in MRP-47 are considered to be equally applicable to 23 the draft guide methodology. Some, but not all, of 24 the issues raised in the MRP-4 7 have been specifically

• 25 addressed in the draft guide.

NEAL R. GROSS Based on these, the MRP COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

82 1 would like to see clarification on the remaining 2 issues included in Draft Guide 1144 and the supporting 3 document." 4 Our response was that the level of

  '5 analytical detail discussed in the additional items in 6 MRV-4 7        revision    1    are    beyond       the  scope   of       this 7 regulatory guide.

8 The third issue was the comments were 9 asking to provide a guidance for nickel chromium 10 alloys and this comment was incorporated. We saw that 11 we have the EPRI methodology developed for the nickel 12 based alloys and we have regulatory position 3 on that 13 reg. guide that addresses this. 14 The fourth comment is on the burden due to 15 the increasing location required to be analyzed. The 16 practice will lead to more analyzed piping, reg. 17 locations to more installed pipe width restraints and 18 to the signs that will be more detrimental for normal 19 operating conditions. The NRC staff will consider a 20 justified modification with appropriate technical 21 bases of the fatigue criteria for fossilation of pipe 22 breaks implementation of the current criteria, saw a 23 significant increase in the number of required pipe 24 with restraints .

• 25 The fifth issue is the same commenter, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

j I 83 1 believes that the alternative methods for fatigue 2 analysis in NUREG CR-6909 and draft Guide 1144 are too 3 conservative and should not be used for the design of 4 new reactors. 5 Our response was is that the staff 6 position is based on a 95th percent confidence, that 7 there is less than 5 percent probability of fatigue 8 crack initiation. And implementation of this criteria

  ,9     results in a carbon and low-alloy steel air curves 10      which are less conservative than the existing ASME 11      Codes.

12 The last comment was from ASME that 13 basically ASME will continue to develop a code case 14 that will cover alternative ways of addressing the 15 impact of light water reactor environment. And 16 they're saying that the code case will be issued in 17 early 2007. Once these code cases are issued, ASME 18 will request NRC to endorse these codes in the 19 revision Reg. Guide 1.84. And we agree with that. 20 The NRC staff will consider endorsing available ASME 21 code cases through its normal process for revising 22 Reg. Guide 1.84. 23 Conclusion, the Reg. Guide 1.207 is ready 24 for issuance and the final Reg. Guide and NUREG

• 25 reports reflect a resolution of these comments and the NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

84 1 final Reg. Guide and NUREG will be published by March 2 2007 and so we're seeking ACRS concurrence to publish 3 a final effective guide.

  .'4                    Any questions?

5 DR. BONACA: Just a question regarding 6 your last -- the sixth issue. 7 MR. GONZALEZ: Yes. 8 DR. BONACA: Talking about revising 9 Regulatory Guide 1.84. Can you expand on that? 10 MR. GONZALEZ: Regulatory Guide 1.84 is a 11 reg. guide that is updated each time for any new code 12 cases. The NRC reviews and sets 13 DR. BONACA: Okay . 14 MR. FERRER: Yes, this is John Ferrer. 15 The intent of this statement is we'll look at what 16 ASME puts out as a code case and if we think it's 17 appropriate, we'll endorse in the update of 1.84 and 18 maybe get rid of the reg. guide, but right now we 19 can't wait for ASME to put something out because we 20 have on-going reviews and we need a position 21 established to do these reviews with. 22 MS. VALENTINE: This is Andrea Valentine 23 from the Office of Research. This is normal 24 procedure. There's a reg. guide that endorses Section

• 25 11 and O&M Code. So this is nothing different than NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

85 1 what we normally do for code cases. 2 DR. BONACA: I want to make sure that 3 revising that will not mean to modify what you are 4 proposing in this NUREG. 5 MR. FERRER: Well, we could possibly, you 6 know, ASME is going to come up with a position. We 7 don't know whether it's going to be exactly the same 8 as our position or it's going to be a different 9 position. If they make a good enough argument that 10 their position is better than our position, we may 11 consider adopting the ASME position. But I mean that 12 would be a tough case for ASME to make, once we get 13 the reg. guide out . 14 (Laughter.) 15 MS. VALENTINE: And also to add to that, 16 if you recall earlier from Hipo's slide, this has been 17 deliberated for a number of years over 25, so this 18 wasn't something we just did in a vacuum and decided 19 to take this route because it was a short-term issue. 20 It has been something that was discussed for many 21 years. 22 DR. BONACA: Regarding issue five, I mean 23 the contention here is that the NUREG will impose 24 excessive conservatism and you disagree. You don't

• 25 have the basis for that statement.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com I

86 1 MR. FERRER: . *Well, let me explain the 2 basis for that. There's a lot of-- a lot of comments 3 we're arguing that we impose an overly conservative 4 position in this reg. guide and what we're trying to 5 point out here is the basis for our position which is 6 a 95/5 with a shift in the current position of ASME 7 and it's actually, if you apply it to air curves, it 8 results in a curve that's less conservative than the 9 ASME already has. 10 DR. BONACA: I guess I was trying to 11 understand how the -- if they agree with your view. 12 MR. FERRER: You've got them up next. 13 (Laughter.) 14 CHAIRMAN ARMIJO: They' re coming. They're 15 coming. 16 DR. BONACA: Okay. 17 CHAIRMAN ARMIJO: Okay, if there are no 18 other questions, the next speaker will be Mr. Ennis of 19 ASME. 20 At least that's what's on the agenda. 21 (Pause.) 22 MR. BALKEY: My name is Ken Balkey and I'm 23 Vice President of ASME's Nuclear Codes and Standards. 24 And we appreciate the opportunity to meet with the

• 25 Advisory Committee on NEAL R. GROSS Reactor COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

Safeguards, (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

87 1 Subcorrnnittee, on Materials,* Metallurgy and Reactor 2 Fuels. 3 What we'd like to do is address our 4 viewpoint and corrnnents on the proposed reg. guide 5 which is DG-1144 as issued for public corrnnent. 6 Next slide. 7 What I'd like to do is -- this is a very

  *8 broad issue that impacts particularly our ASME Section 9 3 of boiler and pressure vessel code.                     Joining at the 10  table with me are Kevin Ennis who is the Director of 11  ASME Nuclear Codes and Standards and is my counterpart 12  as     the ASME staff.             I'm the Senior Volunteer for 13  Nuclear Codes and Standards .

14 Joining me are Bryan Erler who is the Vice 15 Chair of our Board on Strategic Initiatives and he's 16 been a long-time member of ASME on the Boiler and 17 Pressure Vessel Codes Subcorrnnittee 3. 18 Dr. Chris Hoffman, who is a member of the 19 ASME Boiler and Pressure Vessel Main Corrnnittee, 20 Standards Corrnnittee is with us and he's also a member 21 of the Code Subcorrnnittee and also a member of many 22 other subgroups and working groups in Section 3 as 23 well as other parts of the code. 24 And then finally, Mr. Charles Bruny, who

• 25 is a member of the ASME Subgroup on Design and he's NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

88 1 past chair of the working group on vessels. 2 The reason we have this team assembled, 3 first of all, I'd like to pass along the regrets of 4 Mr. Richard Barnes who is the chairman of Subcommittee 5 3 and his schedule prevented him from being able to 6 join us here today. 7 The folks who are here are true experts 8 from Section 3 are Mr. Erler, Dr. Hoffman and Mr. 9 Bruny. But in terms of background, my own background, 10 well, I've done a significant amount of work in risk-11 informed, in-service inspection and other risk-12 informed initiatives prior to my role here with the 13 Board on Nuclear Codes and Standards. I built plants 14 back in the '70s and I actually applied the rules. We 15 did the very first plant, B317 back in 1972 for the 16 Trojan Plant. As we were transitioning from B311 to 17 B317 and then to Section 3, I have my own personal 18 insights about what's happening here with the proposed 19 rules and what it means when you actually come and 20 you're going to actually physically build a plant and 21 the challenges you get into. 22 Mr. Erler was a senior executive with 23 Sargent Lundy and also built reactors. Dr. Hoffman 24 and Mr. Bruny are also long-term members involved with

• 25 designing and building plants and components.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. And (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

89 that's going to be one of -the key elements you' 11 hear from us is that there's a lot of good work that was

 --presented here this afternoon, but there's a practical aspect        of   translating       this     into       use  in    actually designing and building a plant that really needs to be given serious consideration.

Next slide, please? I'm sorry, we already had that slide. What I'd like to do is just take one minute, not to just -- I know you're familiar with the codes and standards, but I would like to touch upon our organization and how we do our work relevant to the proposal in front of you . The other issues we did put a letter in in September, as you all well know, ASME, we wanted to have a chance to review this reg. guide and the proposal in detail and come up with a consensus technical position, but the reg. guide came out right before our Nevada meeting and we put our letter in asking for a 60-day extension in order that we could have such discussion at our meeting in Louisville, Kentucky about a month ago. But because of time schedule, we were not granted that request, but there are some comments that we have gathered from our

• colleagues within Subcommittee 3 related to this draft NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

    'I I'

I 90 1 guide that we would like.to go over. 2 And then we'd like to go over and give 3 some background on efforts that we've done addressing 4 the impact of fatigue. There's three approaches that 5 have been looked at and we continue to look at and 6 we' 11 have a technical discussion on each of those 7 before we present a summary and some future actions. 8 Next slide. 9 On organization, just we have, of course 10 we write codes and standards beyond just nuclear power 11 plants. We have about 3,000 volunteers writing codes 12 and standards for pressure devices, elevators, lifts, 13 screw fasteners and a whole host of number of 14 applications. 15 In our nuclear codes and standards, one 16 unique feature is that Section 3 and Section 11 are 17 two of the 12 sections of the boiler and pressure 18 vessel code and so as we look design roles or 19 materials or certification requirements, we just don't 20 it within the nuclear. It's done, any technical 21 requirements coming forward go in front of the Boiler 22 and Pressure Vessel Standards Committee so that our 23 practices can be reviewed by experts in similar areas 24 from other industries who are addressing the same

• 25 types of issues, whether it be fatigue or corrosion or NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

91 1 other design factors*that* one would want to take into 2 account . 3 And it does come in because one has to 4 remember that the plants we are operating today were 5 built on design requirements that were put in place in

  .*6 the 1960s and 1970s for the most part, and those rules 7 evolved from the use of the B31 line power piping code 8 as well as Section 1 and Section 8 for the vessels.

9 So we -- our nuclear -- we've adopted those prior 10 experience where there's been relevant experience for 11 many, many years. That plays into what we' 11 be 12 discussing here today. 13 I just wanted to mention that the Section 14 3 and 11 are part of this other organization that 15 reviews it from broader than just a nuclear power l6 industry. 17 The next slide is just a verbal 18 description of some of the acronyms that make up the 19 nine groups that report to the Board on Nuclear Codes 20 and Standards. The next slide deals with the 21 consensus process. There were comments made about 22 hey, we've worked on this for 25 years. We haven't 23 come to a consensus and I would really like to ask 24 Kevin Ennis to go over some points relative to ASME,

• 25 what it means when we achieve consensus or what it NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

92 1 means when we don't achieve-consensus. So Kevin, if 2 you would be kind enough to do that. 3 MR. ENNIS: Thank you. All of our 4 committees, all of our volunteers in nuclear codes and 5 standards operate in an open and transparent process 6 and that process is geared to achieving consensus on 7 what appears in our codes and standards. Now these 8 volunteers are made up of world experts. They're from 9 all over the world. They come to our codes and 10 standards meetings and if you know the hierarchy of 11 our committees, the further down you drill into the 12 committee structure, the higher the concentration of 13 expertise, so that when you're really down into the 14 people who do fatigue analysis, that's what they do 15 and they come from all over. 16 We have much international participation 17 and we always stress that we rely on industry to 18 support this participation. We don't pay any of these 19 volunteers. And I would also like to take a second to 20 thank the NRC for their participation in ASME codes 21 and standards. 22 But the achievement of consensus from the 23 users' perspective, you only see the consensus 24 results. But there is a whole process that the

• 25 volunteers go through and the first thing that they NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

l r I I 93 1 have to achieve consensus on *is the technical basis to 2 respond to identified means. 3 DR. WALLIS: That my question* here. 4 Doesn't this work that we just heard about provide the

  .*5     broader technical basis than you had before?

6 MR. ENNIS: It provides some data that has 7 been developed over time, but we also look at our past 8 experience. We never forget our history. As Ken 9 quite rightly noted, the original new plants are B311 10 plants. We still build coal-fired plants today to 11 B311, the piping. And we have great success with 12 them. As we identified needs for the nuclear 13 industry, B317 was developed -- 14 DR. WALLIS: Coal plants don't have 15 pressurized water reactor environment. 16 MR. ENNIS : No, they don' t, but there are 17 other B31 documents that have dramatic impact on 18 environmentally-caused failure mechanisms and we rely 19 on those people too. One of the sections of the 20 boiler code, Section 8, and its piping division, B313, 21 they have lists of failure mechanisms that are 22 dramatically long, much longer than what you see in a 23 nuclear power plant. 24 We do rely on that expertise and

• 25 experience. They operate at much higher temperatures NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

I I 94 1 and pressures and much *

• more severe chemical 2 environments. So we do have their expertise is also 3 looking at this. And we rely on that heavily and they 4 learn from us. We started out with the risk-informed 5 before they did. So it's a mechanism whereby 6 expertise that is -- grows up in different industries 7 can exchange information and ideas and solutions to 8 problems.

9 And when you read the statement, identify 10 technical basis, implicit in that statement is that 11 there is consensus on the need and I think you' 11 hear 12 later today or later in our presentation, that really 13 hasn't been achieved yet. And it's not only in 14 nuclear, it's also in the design experts that come 15 from outside nuclear that looked at our work that we 16 talked to during boiler code week when all 12 17 subcommittees meet. 18 So there is a lot of discussion going on 19 and still at least in the limited amount of discussion 20 and exposure I have to the experts, because now I'm 21 director, I don't, I don't perceive consensus has been 22 achieved on the need. And that's one of the things 23 that's taking so long. And, once that happens, then 24 you can get a result and that's the consensus

• 25 everybody sees outside of the committee structure.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

95 1 And that consensus we always* say must be technically 2 accurate, must obviously assure adequate safety, but 3 must be practical and workable.

  *4                   And another one of the comments you '11 5 hear from the other presenters from ASME goes along 6 the idea of practical and workable.                     Are we really 7 going to achieve good by making this change?                     And, is 8 our achievement worth the cost?

9 DR. WALLIS: Well, presumably, a curve 10 that's there now is practical and workable and if you 11 replace it with another curve it's just as practical 12 and workable as the previous one was. 13 MR. ENNIS: Not necessarily, and I' 11 14 leave up to the design experts to get into that 15 detail. But at least they raised enough questions in 16 my mind to say is it, is the new curve, practical and 17 workable? But I'll leave it up to them to bring up. 18 DR. WALLIS: If the process is the same, 19 of just taking the -- 20 MR. ENNIS: No, it's, it would not be. 21 DR. WALLIS: -- if the process is the 22 same, but you'll tell us 23 MR. ENNIS: There's more to it than just 24 the curve .

• 25 DR. WALLIS: -- you'll tell us.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. Okay. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

96 1 MR. ENNIS: And what I do, any my role 2 with my staff, is we provide the structure and the 3 administrative support. Give the experts the 4 opportunity to come to consensus and hopefully try to 5 corral them into doing that. And with that, I' 11 pass 6 it back on to Ken. 7 MR. ERLER: Well actually on to me. 8 MR. ENNIS: Yes. Mr. Erler is going to 9 review the open comments, some technical comments we 10 gathered. The reason we call them is open comments is 11 that they were not in our paper, they have come from 12 deliberations we've had and they're comments from the 13 members. They're, it's not a, we haven't had a 14 consensus to say these, there's a consensus, everybody 15 agrees these are the comments on the Reg Guide -- 16 DR. WALLIS: It doesn't look like a 17 consensus at all, this slide here. 18 MR. ERLER: The process, really, it's a 19 very unique process and I think that was why it was 20 important that Kevin address the fact is that we have 21 experts from around the world that are experts in all 22 various industry and it really provides a strength in 23 the code. 24 And the number one comment that we're

• 25 dealing with is we've been working on it for 25 years.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

97 1 The phenomena we have no disagreement with. It 2 exists. The issues that we're dealing with are we've 3 had no failures with regard to environmental fatigue 4 impact. We looked back at our operation and the 5 answer that was presented here today was, the EPRI 6 research or there's a few of them. And they really 7 were more related with corrosion or corrosion/stress 8 corrosion and fatigue interaction. It was not a pure 9 fatigue issue. 10 And many times, the fatigue issues -- not 11 fatigue issues, other failure issues are dealing with 12 vibrations or other related type phenomena and 13 separating it out, we really look at the fundamental 14 experience of today that the operating plans have been 15 served well by the design basis we've had for a number 16 of years. But we've looked very carefully. We've 17 done research, we've assigned various task groups. We 18 brought people in from around the world and we can't 19 all agree amongst these experts that there's a need to 20 change, that there's sufficient margin in the design, 21 has proven itself to be very effective. 22 The other item really is how does it 23 apply, you know? Some of the research that we have, 24 there's obviously these specimens don't reflect

• 25 environment that primarily piping or vessels are in, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

98 1 where the internal diameter-of the components are the 2 ones that are exposed to the environment, not the 3 whole metal. 4 DR. WALLIS: Could you explain something 5 to me? I sort of got the impression from what was 6 presented, the Argonne work, that your curves are 7 based on tests in air. 8 MR. ERLER: That's correct. 9 DR. WALLIS: How do you then account for 10 the additional effects of putting it in water with 11 various amounts of oxygen and so on in there? 12 MR. ERLER: The original criteria that 13 goes back to 1960 -- 14 DR. WALLIS: Twenty and 15 MR. ERLER: It was the 20 and 2 factor 16 that we put in. 17 DR. WALLIS: Is that good enough today? 18 MR. ERLER: That's correct. You've got to 19 look at the methodology that was used for analysis. 20 The methodology that was used for the margins that 21 exist elsewhere in the code and the reluctance to 22 really start taking out margin in the code or adding 23 in for special analysis that was totally done in the 24 lab .

• 25 So that's where we're looking at, trying NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

{202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

t: 99

  .*1    to bring together an operating experience and the lab 2    data that we have.            We're not ignoring it as will be 3    outlined        in   our   approach        that     we   have   proposed.

4 Twenty some years of working at it, we've had a lot of 5 heated discussions from many, many experts that have 6 brought forward some very, very valid points. 7 The issues that we're dealing with are 8 just some of this data is not the same as was 9 presented here. The methodology that was used for the 10 dry test, with this 25 percent drop rate methodology i1 is not the same as the crack growth. So there's some 12 adjustment that has to be done and then analytical 13 figuring of the F~ factor. 14 So there's a lot of analytical 15 manipulation of data that may not apply to the actual 16 components and we haven't seen the failure in the 17 plants that we have -- 18 CHAIRMAN ARMIJO: Now didn't the Argonne 19 researchers do the manipulation and share that with 20 you and did you find fault with the way they did it? 21 MR. ERLER: Yes, well, no. There's a lot 22 of arguments with the way -- that's why you have the 23 dispute in these meetings. There's some fundamental 24 disagreements with how it's being done, how it's being

• 25 adjusted and does it really represent what you have in NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

{202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

100 1 today's environment? 2 DR. BONACA: Could you comment on bullet 3 number two. I'm interested in understanding that 4 better. 5 Environmental fatigue affects only inside 6 surface -- 7 MR. ERLER: We are dealing primarily -- 8 our fatigue is really dealing with the inside surface 9 of piping and so therefore you're not dealing with 10 components that have been submerged in water or in 11 oxygen or other environments that you have. And so 12 when you apply it to the methodology that you have, 13 piping analysis is a structural analysis. You don't 14 look at internal and external. You have to apply it 15 to the whole component. 16 And so here you have a bending component, 17 bending, not bending on the piping, but bending within 18 the wall thickness that we're applying a penalty on 19 across the board. So that's part of the application 20 problem that you have here. You've got realize some 21 of the design, for a vessel, it's pretty simple. You 22 have certain rules and certain -- that's in the code 23 rules and we've expanded it to cover phenomena, but 24 the fact of the matter is that when you start applying

• 25 this analysis, as even stated here, that you need to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234*4433 WASHINGTON, D.C. 20005*3701 www.nealrgross.com

i. 101 1 go into a very detailed finite analysis, finding out 2 exactly the stress concentrations, the cycles that you 3 have to go with. And it doesn't really apply to the 4 same methodology you really had in the code directive. 5 So we have a way of translating that. That's what 6 we've been working on is arguing how you translate 7 that into applications into today's analysis. 8 MR. BRUNY: Could I add to that? Chuck 9 Bruny. Current methods in today's piping analysis is 10 done with some standard equations that are in the code 11 and stress indices that are developed for various 12 components in the piping system and for various 13 loading conditions. Now this stress index is a way of 14 getting the maximum stress somewhere in that component 15 that is generated by that load or that condition. 16 These are then are all added together. It may not be 17 the stress at the ID surface and the stresses from one 18 load condition may not occur at the same location as 19 another. So the industry today works with a 20 simplified approach which comes up with very 21 conservative stress evaluations for most of the piping 22 components. 23 The addition of the Fen approach and the 24 impact is that many of these locations analyzed under

• 25 this current methodology will prove to be unacceptable NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I: I' 102 1 and therefore significant detail analysis will have to 2 be undertaken in order to evaluate the stresses at 3 specific locations on the inside surface of these 4 components throughout the piping system in order to

  *5    apply the Fen approach in a way that isn't so overly 6    conservative        that    it    has    dramatic      impact    on      the 7    piping.

8 CHAIRMAN ARMIJO: Do you know how to do 9 these analyses? 10 MR. BRUNY: Yes. 11 CHAIRMAN ARMIJO: So it's the amount of 12 work and the amount of detail you have to do. 13 MR. BRUNY: It's a significant amount of 14 additional work over and above current methodology to 15 do that and the approach that was taken in life 16 extension was a very limited number of locations were 17 evaluated in the life extension analysis and 18 application of Fen and some of those did use this 19 extensive analysis, but on a very limited number of 20 locations, not the entire piping system for a plant. 21 CHAIRMAN ARMIJO: When you did not 22 particular analyses did you compare them what the 23 standard code process would predict? I mean were they 24 consistent? Was the standard code analysis

• 25 conservative compared to NEAL R. GROSS the more COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

sophisticated (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I'

    !I 103 1    analysis?

2 MR. BRUNY: I haven't looked at the 3 detailed analysis or detailed results. What I have 4 heard is that the Fen approach, in general, would give 5 higher fatigue usage factors than the code analysis. 6 In other words, there were more locations, many more 7 locations that would have a fatigue usage factor 8 higher than the .1 value that is the current threshold 9 for determining a potential pipe break location. 10 MR. ERLER: Let me expand on that a little 11 bit, because that's a -- the Fen approach and you look 12 back in '91 and a lot of this was done, was identified 13 as an issue in pursuit, primarily focused on analysis 14 for life evaluation where you go in and make sure, 15 find out where you are in the plant and that's why in 16 all of the license renewal, you find the plants are 17 acceptable, so the answer to that is I say yes, 18 because every place you've applied it in plants for 19 license renewal or for existing plants that are 20 currently certified have been acceptable. 21 So it's a lot more work, but it was very 22 important in operating plants to be able to verify 23 that for the added 20 years that you were putting on 24 it. I think the difference we're focusing on here,

• 25 Section 3, we're talking about design, up front design NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234*4433 WASHINGTON, D.C. 20005*3701 www.nealrgross.com

I' 104 1 where you don't know necessarily. You're designing 2 something you don't want to go into detail analysis 3 evaluating research and pick out design is

  .4    significantly different than evaluating the impact.

5 And therefore, we need a design approach which is, has 6 the margin in there that we know can be handled by the 7 various conditions and environment and cycles that we 8 have. 9 DR. WALLIS: Can we talk more about this 10 Fen? As I understand it, there's a curve that you get 11 from tests in air when you do tests in other 12 environments such as PWR water, different 13 temperatures, you get some other data. All Fen does l4 is tells how much the curve moves when you move to a 15 different environment. That seems to me an 16 appropriate way of treating the data. Now you may be 17 arguing about how practical it is, but I don't see how 18 you can argue it's not an appropriate way of treating 19 the evidence. 20 MR. ERLER: It may be. If you look at our 21 last comment that we have here is that the 22 implementation of the code design rules has a number 23 of issues. Those issues were identified in the EPRI 24 report MRP47 .

• 25 DR. WALLIS: It's the application of these NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

105 1 factors you complain about, not the way that -- it's 2 not an inappropriate way of treating the data, are 3 they? 4 MR. ERLER: It's the conservatism in it 5 and the application of it in a design environment in 6 designing a new component. 7 DR. WALLIS: The application is what you 8 object to.

  *9                  MR. ERLER:     This write up was significant, 10  going into a       lot of detail on the difficulties of 11  trying to apply it and it is appropriate.                 Where ASME 12  is coming from and the debate that we have in all of 13  our committees is for what benefit?                    If we haven't 14  seen a problem 15                   DR. WALLIS:        For public safety, you have 16  a better --

17 MR. ERLER: Well, then let's go back-to 18 our item, bullet two here. One of the things that

 !9  we're very much concerned with, those usage factors is 20  the fact that we're going to end up with a lot more 21  pipe       restraints   installed,        a    lot   more in-service 22  inspection required because of usage factor being up.

23 And you're going to have a lot of other issues for, 24 again, very little benefit .

• 25 It kind of reminds a lot of our people NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

106 1 that are around the table of where we were in the '70s 2 and '60s where we were putting in more pipe restraints 3 because of increase in seismic analysis response 4 specter, decrease in damping values that were allowed, 5 and then 10 years later we spent another bunch of 6 money taking it all out, because what we're doing is 7 we're constraining a system that would prefer to be, 8 have some more flexibility to respond to the thermal 9 and the dynamic response. 10 So it has a possible negative safety risk 11 that we have and that's probably the more stronger 12 opinions at the table when you're debating it. It's 13 not the fact that we have to work more at it because 14 most of the people there probably get paid more for 15 doing that analysis. The fact is that it would be 16 unconservative. The application of Fen for evaluation 17 of existing plants and life prediction is a very good 18 approach. It's applying it as a design approach that 19 we object to, especially when you look at it and it 20 hasn't had been proven that the existing design 21 approach is a problem. 22 And we're going to get into more detail 23 when Dr. Hoffman goes through the approaches that we 24 have. Like I say, we haven't given up on the fact

• 25 that we need to address this.

NEAL R. GROSS It's how do we address COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

107 1 it, what is the issue we need to address and what 2 approach should we use? 3 CHAIRMAN ARMIJO: But if you wanted to 4 freeze the approach with the codes that are in 5 existence today, the ASME curves, would you also 6 freeze all the analytical procedures to the state-of-7 the-art at the time that they were imposed and not

  '8 allow        any    more    sophisticated           analysis?        Because 9 otherwise you're eroding margin.

10 MR. ERLER: That's right. There's a lot 11 of debate on that and you can't -- you can't freeze 12 either, really. What we try to have is some kind of 13 standard, codes and standards stability to deal with 14 and some kind of oversight with regard to the 15 analytical capabilities that you have. But not for 16 every Class 1 piping system do you want to have to do 17 it, or every valve that you have to do it. 18 DR. WALLIS: No debate that in the 19 environment and in the PWR the metal is more prone to 20 fatigue than in air? There's no debate about that, is 21 there? 22 MR. ERLER: I think the statement is we 23 agree that that phenomena exist. Does the current 24 standard cover --

• 25 DR. WALLIS: The current standard doesn't NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I 108 1 take account of that,* does it? -- 2 MR. ERLER: Not explicitly, but it does 3 state in the criteria document that the 20, that will 4 account for environmental effects. 5 DR. WALLIS: It's good enough to take 6 account of it. 7 MR. ERLER: That's what currently in our 8 criteria document. 9 DR. WALLIS: Twenty is good enough. You 10 don't need to adjust it any other way. That's your 11 position? 12 MR. ERLER: Let me say this. We really 13 should go through the rest of our position. Because 14 we're not digging our heels in on this here. We just 15 want to get to the right solution. 16 DR. WALLIS: I thought you were. 17 MR. ERLER: No, no, no, no. 18 DR. WALLIS: You are flexible on this? 19 MR. ERLER: It's a very complicated area 20 to deal with and finding the right solution, that 21 doesn't bring the bad stuff with the good solution. 22 DR. WALLIS: There is hope for compromise 23 after 25 years? 24 MR. ERLER: I believe there is. So we've

• 25 dealt with, I think does NEAL R. GROSS the COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

implementation (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

109 1 approach result in*** unnecessary code, regulatory 2 burden? This is the analysis and then we're talking 3 about then the implementation side. So I guess that 4 really covers most of the open issues. 5 DR. WALLIS: Have you evaluated that? 6 The burden and the benefit? Is that being evaluated 7 or are you just raising a question? 8 MR. ERLER: We're tying it together with 9 the bullet above it, that the fact of the matter is it 10 does take more analysis in order to bring within 11 allowables just like potential new allowables like 12 Chuck Bruny stated. 13 DR. SIEBER: That you quantified that 14 additional effort? 15 MR. BALKEY: Let me try a different tack 16 here because it came up in the discussions here. When 17 we did the risk-informed in-service inspection, more 18 than 90-some reactors have implemented here in the 19 United States as well as six or seven other countries, 20 in a way that was -- that assessment was almost a 21 check on the plants that were operating. How does the 22 risk from the operation of these pressure boundary 23 components, how does it compare to the risk for other 24 contributors to overall plant safety?

• 25 When we did the risk-informed ISI where NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

110

  .1 you're combining the probability of failure at various 2 locations and at that point you already have a fixed 3 design.         It was done to whether it was B311, B317 or 4 Section 3,         and you're doing this assessment.                     One 5 method uses policy fracture mechanics,                     another one 6 went through an entire operational history, and what 7 you find out that the risk,                 first of all,      the risk 8 from pressure bond through failures using this code is 9 a small contributor.             It is not a large contributor.

10 DR. WALLIS: Small has been used before 11 today. How small is it? 12 MR. BALKEY: We're talking definitely less 13 than 10- 6

• 14 DR. WALLIS: On CDF?

15 MR. BALKEY: On CDF. Now let me come back 16 to it. Even if -- I don't want to argue how low is 17 low enough, but when you look at where the predominant 18 contributors were to the risk from the piping, it's 19 not from fatigue. It's from the things where you may 20 have the possibility of back leakage through a check 21 valve. It may be in thermal stratification that you 22 may be predicting. It may be that hey, we have an 23 environment 24 DR. WALLIS: That's thermal fatigue or is

• 25 this a stressor solution we're talking about?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

111 1 MR. BALKEY: You could have a -- if a 2 check valve started leaking, you'd end up with thermal 3 striping and you'd end up with a very -- 4 DR. WALLIS: It's a fatigue problem? 5 MR. BALKEY: Pardon me? 6 DR. WALLIS: A fatigue problem. 7 MR. BALKEY: Yes, but the issue is not the 8 calculation of fatigue, the issue is the loading 9 environment itself, once you get into a loading 10 environment that's causing that challenge. 11 And the point I'm trying to make is that 12 even when you I went through the regulatory 13 assessment. The statement was made that when this -- 14 the impact of environmental fatigue, even for life 15 extension, the NRC did risk analysis calculations to i6 show that it's acceptable to safety. So the question 17 you have to ask like I said, we're not trying to say 18 you don't address these factors. The question is do 19 you do it here in design or do you address it through 20 your in-service programs. And that will come bearing 21 out. 22 So therefore, the NRC and the industry 23 have worked very hard to focus our resources where it 24 matters . And one question you have to put on the

• 25 table is are we asking NEAL R. GROSS the industry COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

to do a (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

112 1 significant amount of.work on an area where the risk 2 may be low . 3 DR. WALLIS: The question I would ask is 4 how big does this F have to be before you are forced 5 to make a change? 6 MR. BALKEY: What we're saying is the 7 operating experience today is not bearing that out. 8 DR. WALLIS: You say the influence is so 9 small that it's not important. How big would it have 10 to be? Would it have to be twice as big or something 11 before you say you have to do something? 12 MR. BALKEY: Well, I'll respond when we 13 look at Section 11 . Section 3 is talking about 14 design. If I go over to Section 11, as soon as we 15 have experience and our Section 11 group is dealing 16 with all the different cracking mechanisms that are 17 coming and we have reached consensus on a number of 18 code cases in order to change the inspection and the 19 repair and replacement of that equipment. But it 20 comes back to what Kevin Ennis said, that the 21 challenge and the question we have is is the 22 information that's available, does it warrant going 23 back to do all this work and is it going to add 24 additional burden?

• 25 DR. WALLIS: The problem I have with your NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

113 1 presentation so far is you really haven't demolished 2 the view of ANL and the NRC. You've talked about a 3 lot of things, but you haven't convinced me that in 4 any way they're at fault. 5 MR. BALKEY: I think that the position 6 that we're saying is the fact that in design part, we 7 have found that the design of the plants you end up 8 with fatigue being adequately covered by the process 9 originally set up. 10 DR. WALLIS: Are you going to show that 11 somehow? 12 MR. BALKEY: The way to keep that going 13 forward is to keep an eye on it through the monitoring 14 program that you have in place, rather than trying to 15 make, squeeze a more conservative design on existing 16 component system. 17 CHAIRMAN ARMIJO: But if you do a better 18 job in designing piping by using data, modern data and 19 modern analytical procedures, somewhere along the line 20 you ought to be able to say I don't need to do as much 21 in-service inspection. I don't -- there will be a 22 benefit coming out of it, even though there's an 23 upfront cost. I agree there will be an additional 24 cost, but it seems to me that if we know these

• 25 environmental effects exist, NEAL R. GROSS and COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

we measured the (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

114 1 phenomena. We've got data. It seems strange that we 2 wouldn't use it along with our more modern analytical 3 procedures. You know, just everything improves. 4 MR. BALKEY: And we are commit ted to 5 working with everybody to look for that solution. 6 CHAIRMAN ARMIJO: And a benefit of this, 7 you might have a much better piping design by virtue 8 of doing the more -- using the modern data and the 9 modern analytical approaches and the payoff could be 10 in less in-service inspection or more reliable piping 11 system. 12 I just-- or both. I can't see why you're 13 just looking at it as just a burden and we ought to 14 stick with 15 MR. BALKEY: Except that the Fen procedure 16 or the revised fatigue curves may not be the solution. 17 CHAIRMAN ARMIJO: There may be other 18 solutions. 19 MR. BALKEY: It's a better solution than 20 we've -- and that's what we want to work for. 21 CHAIRMAN ARMIJO: I think we should move 22 over now to 23 MR. BALKEY: Dr. Hoffman is going to go 24 through a little more technical information on what

• 25 ASME has done.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com i'

115 1 DR. HOFFMAN: This you've already seen 2 and heard previously. There has been activity within

  '3 the ASME Code Committees and initially with the PVRC 4 Steering Committee on Environment for a long time.

5 The only thing that I would like to highlight from 6 this slide is that there are a couple of items, the 7 introduction of Appendix and Code Case N643. There 8 were specific actions that the Code Committees did 9 come to agreement on and published new rules to 10 address environmental effects in both of those items. 11 The N643 code cases is of note because it 12 allows you to decide, based on the environmental 13 conditions and the transience occurring in a component 14 whether or not the environmental effects need to be 15 considered. It kind of turns them on or off, 16 depending on the local conditions. 17 Next slide. 18 Just earlier this year, the Section 3 has 19 a task group on trying to decide what to do about 20 environmental effects. They just completed their 21 efforts earlier this year and these were the 22 recommendations that they forwarded to subgroup design 23 of Section 3 to decide whether any changes needed to 24 be made to the design rules or to adopt new fatigue

• 25 curves that incorporated environmental effects or to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I, i 116 1 use an Fen type approach. These are the various i terns 2 that we've heard about earlier today, either changing 3 the curves or the F~ effect. 4 So subgroup design is still looking at 5 these. 6 DR. WALLIS: It seems that option 2 here

  *7    would involve some change in the fatigue curves that 8    ASME recommends.

9 DR. HOFFMAN: Right, there have been -- 10 DR. WALLIS: Factor 20 would become 30 or 11 something or whatever. 12 MR. BALKEY: Or the fatigue curves -- 13 DR. WALLIS: Right. 14 MR. BALKEY: There have been proposals to 15 introduce new curves that have the factors built in. 16 MR. BANERJEE: What do you mean by without 17 the extra conservatism in the guide? 18 MR. ERLER: That particularly was 19 addressing the-- there's a number of factors that are 20 included in the guide in terms of applying Fen* If 21 you look at some of the early research that you had 22 and now the subsequent research that would indicate 23 the factor should be 1.5 as opposed to 2. 24 DR. WALLIS: Is the conservatism in this

• 25 95th percentile or moving the curve over further than NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

i I 117 1 it needs to be? 2 MR. ERLER: Well, you know, obviously, 3 **they've moved some of the curves, the stainless. steel 4 down and they've moved some of the carbon steel up and 5 -- but the margin that they're aiming for has been 6 consistent and the margin is, we think, is too 7 conservative when you consider you're improving your 8 knowledge that you have and you're improving what 9 you're considering in your analysis, so that some of 10 that margin should be reduced. 11 So part of the debate, if you're going to 12 apply it, what should that margin be? 13 DR. WALLIS: Isn't the margin based on 14 some statistical evaluation based on this log normal 15 thing and Monte Carlo analysis? 16 MR. ERLER: That's correct. That's what 17 their analysis was based on. 18 DR. WALLIS: Is something wrong with that? 19 Is that extra conservative to do it -- 20 MR. ERLER: By the time you apply it, you 21 end up with sometimes an increased amount of fatigue 22 usage factor or decrease that causes considerable 23 problems. Some of it goes beyond what would be 24 reasonable in terms of --

• 25 DR. WALLIS: The problem being that you NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I, I: 118 1 have to restrain the pipes more? 2 MR. ERLER: You really get down to details 3 and the usage factor is really connected with a lot of 4 -- the transients that you have and the number of 5 cycles. You end up changing details in order to make 6 7 DR. WALLIS: How is it you know how much 8 these things vibrate in the first place? 9 MR. ERLER: That's the advantage of 10 looking at it in an operating environment because when 11 you know the number of transients, you have 12 monitoring, you have data. 13 When you apply Section 3, you're looking 14 at future. 15 MR. BANERJEE: Where are most of these 16 restraints? I mean the issue that you're bringing up 17 that you have to restrain these pipes more than they 18 are currently being restrained. And that is 19 introducing some problem. 20 MR. ERLER: There are two issues. One is 21 the issue of if the usage factors go up, you have to 22 postulate breaks more frequently. If you postulate 23 breaks, then you've got to put in pipe restraints and 24 protection against those breaks. You can't get at the

• 25 pipe as well for inspection and monitoring very well.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

119 1 MR. BANERJEE: Could you just give us an 2 example of where this would have the most impact? 3 MR. ERLER: On pipes, on class 1 pipes. 4 DR. WALLIS: Main steam line or something 5 like that? 6 MR. BANERJEE: Steam line? 7 MR. ERLER: The surge line has a lot of 8 them on, you know. Feedwater line. 9 MR. FERRER: This is John Ferrer. Could 10 I add a point on this issue you were just talking i1 about? One of our responses to the public comments 12 was that that concern that you could increase the 13 number of postulated rupture locations was legitimate 14 and that if in implementing this new criteria it turns 15 out it causes a lot of extra pipe rupture locations to 16 be postulated, we will reconsider the criteria based 17 on fatigue so that doesn't happen. 18 MR. SIEBER: Then what do you accomplish 19 when you do that? 20 MR. FERRER: There was back in the '80s 21 when they were trying to get rid of the problem with 22 the excessive number of pipe whip restraints, one of 23 the issues that was implemented was leak before break. 24 MR. SIEBER: That's right. That was a

• 25 sensible one.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. {202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

120 1 MR. FERRER: There was another proposal at 2 the time to increase the fatigue usage factor from .1 3 which is the usage you postulate a rupture at to .4. 4 However, at the time this particular change was 5 postulated, we were aware of the concern with 6 environmental fatigue and that the ASME fatigue curves 7 may not be conservative. So we did not accept that 8 change. 9 Now if we're taking care of that problem 10 with the ASME fatigue curves, then a change in the 11 pipe rupture criteria may be appropriate at this time. 12 DR. WALLIS: Is the idea to reduce the 13 burden? 14 MR. FERRER: Well, what we've said in our

 ~5 responses is if the industry comes in and shows us 16 that this is going to cause an excessive number of 17 rupture postulations to occur, we will reconsider the 18 criteria to try to levelize it so it doesn't increase 19 or decrease the burden.

20 MR. SIEBER: Well, you have to balance the 21 increases or decreases in the burden with increases or 22 decreases in the risk and so it takes more to say oh, 23 I don't think we should do that. 24 DR. WALLIS: He' s saying if you know more,

• 25 you might be less conservative.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

    !i II 121 1                        MR. SIEBER:        That's right.

2 DR. WALLIS: Usage factors, but actually, it would make it easier for industry to reduce_ the 4 burden. 5 MR. SIEBER: That's right, and that would 6 be acceptable. On the other hand, just to reconsider 7 what somebody is complaining -- 8 DR. WALLIS: But the claim of the ASME 9 seems to be by implementing these F factors you 10 actually increase the burden. 11 MR. SIEBER: Yes. 12 MR. BANERJEE: And is there a case for 13 thinking that it would reduce the burden? 14 MR. FERRER: Well, if you increase it when 15 you implement the environmental fatigue curves and 16 we've done that in license renewal, a lot of the 17 cases, the change in fatigue usage wasn't that great. 18 So if we were to increase the usage factor for 19 postulating breaks from .1 which is the current 20 position to .4 which was the proposed position in the 21 '80s, this would be about a factor of 4 change in the 22 usage. So you might indeed reduce the burden in some 23 cases. 24 DR. HOFFMAN: Just to complete, you've

• 25 already heard a lot on the three options here about NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

122 1 whether there's a need to make a change. 2 DR. WALLIS: These members of Subcommittee 3 3, are these taken from the nuclear industry? 4 DR. HOFFMAN: Yes. We've also heard 5 recently from the French. They've done a lot of 6 updating of their codes and standards recently in the 7 last few years and they've decided not to include this 8 as a design consideration in their code. Similarly, 9 the Japanese have introduced this as an operating 10 plant evaluation methodology. 11 MR. BANERJEE: Have they heard the view 12 that NRC just put forward? 13 DR. HOFFMAN: The French? 14 MR. ERLER: Both. 15 MR. BANERJEE: And they agree with what 16 was said or they disagree with what was said? 17 DR. HOFFMAN: I'm not sure exactly which - 18 19 DR. WALLIS: Did they see the Argonne data 20 though? 21 DR. HOFFMAN: They've seen the data, yes. 22 They participated in the 23 MR. BANERJEE: The last argument was 24 actually not increase the burden, but may reduce the

• 25 burden because you've got better knowledge now, you're NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234*4433 WASHINGTON, D.C. 20005*3701 www.nealrgross.com I ~

123 1 going through a more sort of a fundamentally sound 2 procedure than you were before, so it may actually 3 reduce the burden, correct? 4 DR. HOFFMAN: Potentially. 5 MR. BANERJEE: Now did they actually hear 6 that view and did they disagree with it or did they 7 agree with it? 8 DR. HOFFMAN: I don ' t think they 9 probably have not heard that view. I think most 10 people's perception in these meetings is initially 11 that the burden is going to be increased. And until 12 you've got through that process -- 13 DR. WALLIS: If the burden was reduced, 14 would that make this more acceptable then? 15 DR. HOFFMAN: The problem is you have to 16 go through the process to find out if that burden is 17 going to be reduced or not. 18 MR. ERLER: The Japanese, they participate i9 significantly on all the code committees, on the 20 Board, as well as on Section 3 and Section 11. And so 21 they're very much involved in all of the data that's 22 being talked about here. 23 The same is true, not as much in terms of 24 active involvement, but the French are always at the

• 25 meetings and following what we're doing.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. They do (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com I'

I 124 1 share their decisions on*it~ 2 DR. WALLIS: Maybe we should move on to

  .3    the next slide and see what the other options are .

4 DR. HOFFMAN: As I said, the adoption of 5 new curves, that's been considered. There have been 6 a couple of proposals brought forward. The problems 7 with this have been identified. They tend to be 8 overly conservative. We're applying a factor across 9 the board for everything and again, the concern that 10 the additional restraints that might be needed 11 resulting from higher usage factors. 12 CHAIRMAN ARMIJO: Is that really the only 13 solution you have, that you'd have to put pipe whip 14 restraints? Couldn't you change the dimensions of the 15 pipe beam or wall thicknesses or just sharpen your 16 pencil and do more detailed analysis? It seems like 17 there's only one outcome and that's a whole bunch of 18 pipe whip that nobody wants. 19 DR. HOFFMAN: The comment we received from 20 Don Landers who chaired the Subcommittee 3 task group 21 was that applying this Fen factor or having new curves 22 isn't going to change the routing of the pipe. It's 23 just going to mean you have to do additional analysis. 24 And I 'd ask if Mr. Bruny would have any further

• 25 comment on that?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I' I I i 125 1 CHAIRMAN ARMIJO: It's additional, more 2 sophisticated analyses that will cost more money. 3 MR. BRUNY: Yes, and I am not privy to all 4 the details, but John mentioned that in the life 5 extension analysis there in several cases there was 6 not a significant increase in the fatigue usage 7 factor, but I challenge whether that was on the same, 8 using the same analytical basis as the original 9 calculations or whether it required to go through the 10 much more extensive analysis in order to achieve that 11 similar result. 12 MR. FERRER: I don't mind answering that 13 question. I thank you for asking it . 14 I think one of the comments I made earlier 15 was that the original design of these plants were done 16 to codes that were back in '69, '71, '74. In the 17 intervening years, in piping, there was a significant 18 change to the criteria related to fatigue that makes 19 it less conservative and that was a change to the 20 parameters that were included in the primary plus 21 secondary stress calculation. And the significance of 22 that is if you exceed a certain value, you apply a 23 strain concentration for the peak stress when you do 24 the fatigue analysis and these strain concentrations

• 25 are the things that really drive the fatigue usage at NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234*4433 WASHINGTON, D.C. 20005*3701 www.nealrgross.com

126 1 most locations.

  .2                  What was done in later codes was to pull 3 out      what  they   call    a   delta     T1     or  a  through-wall 4 temperature transient stress from that equation 10 and 5 that significantly reduced the number of locations you 6 had to apply to strain concentration location.                              We 7 took advantage of that when we were looking at license 8 renewal, so that did have an impact.                    Using the more 9 recent version of the code is not as conservative as 10  the old version that a lot of the analyses were done 11  to.

12 DR. HOFFMAN: The last i tern on the Fen I 13 think most of these points have already been addressed 14 to one extent or another. 15 DR. WALLIS: Why would they make the 16 plants less safe now? I wasn't sure about that. 17 DR. HOFFMAN: That's the additional 18 supports and restraints. 19 DR. WALLIS: They put it in order to make 20 the plants more safe, why would they result in making 21 them less safe? I don't understand that. If they 22 were put there to stop the vibration and the strain of 23 the motion and so on. 24 MR. ERLER: It is the issue of being -- if

• 25 you look at the plants that we ended up with putting NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

127 1 in a lot of supports, constraining the pipe, you have 2 more of a chance of having other stress concentrations 3 due to binding up of the expansion and -- 4 DR. WALLIS: Is it a badly designed 5 restraint system? 6 MR. ERLER: Like I says, it sends us back

  '7    to where we were in the '70s and saying we're really 8    better off getting a more appropriate criteria where 9    we allow expansion, allow supports to be appropriate.

10 DR. WALLIS: That's not a question of* F 11 factors, that's a question of when you use this-- any 12 kind of fatigue method, you're using the right kind of 13 solution to 14 MR. ERLER: Except if you have a greater 15 conservatism, you end up cranking it up more. The 16 other is the issue of access of pipe whip restraints, 17 getting at pipes for in-service inspection is a 18 significant problem, the more restraints you have.: 19 DR. WALLIS: Despite the fact you think 20 this is a lousy piece of work or something that you 21 are going to try to adopt it anyway, is that -- am I 22 just putting it in those terms to try to -- by taking 23 that position to get you to respond. 24 What do you mean by the first bullet here?

• 25 You're going to try to do something similar to what NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I! 128 1 they did? 2 MR. ERLER: That's right. Work with 3 everybody that's working on it, do what we've been 4 doing and try to work our way through some of the 5 fundamental issues that have to be addressed and 6 making sure you've got to remember that the Fen 7 factor is from one specific curve to another issue, 8 depending on the environment that you're in. 9 DR. WALLIS: right. 10 MR. ERLER: And that's a different factor 11 depending on which curve you're starting from and what 12 the environment -- how to apply it is what we'd be 13 working at to making sure that it would be a design 14 practical approach. 15 DR. WALLIS: So in principle, it's not a 16 bad idea? 17 MR. ERLER: Make an adjustment for it has 18 merit. 19 DR. WALLIS: Sounds 20 MR. ERLER: Like I say, the phenomena, 21 we're quite 22 DR. WALLIS: By following this bullet, you 23 might actually reach consensus with the staff. 24 MR. ERLER: You have to sit in the

• 25 meetings --

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

il 129 1 DR. WALLIS: Why don't you do that? 2 MR . ERLER: And to hear the different points of view from around the world and different 4 experts to understand the issues that are technically 5 sound on the table. But there's a feeling you can 6 work it out. It's just going to be a -- 7 DR. WALLIS: The problem I have is it 8 seems that there's an unwarranted reluctance to take 9 this approach. 10 MR. ERLER: No, I don' t think so . I think 11 that it's finding the right Fen and how to apply it. 12 DR. WALLIS: Well, yes, but let's find the 13 right Fen and then apply it if it's a reasonable 14 approach. 15 MR. ERLER: That's correct. 16 DR. WALLIS: You wouldn' t say that' s 17 unlikely. That's something that you could work with 18 the staff to achieve? 19 MR. ERLER: Absolutely. 20 DR. WALLIS: How long would it take? It 21 wouldn't take 25 years? 22 MR. ERLER: Or even 10 years or even 5 23 years. 24 DR. WALLIS: This is like the last time we

• 25 went with ASME and the staff on these issues or issues NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I! 130 1 like this. We simply said you guys ought to go away 2 and work on one of these bullets and make it happen. 3 DR. BONACA: It would be interesting to 4 hear from the staff now. Clearly, there is a search 5 for a consensus and what really troubles me the most 6 is that ASME is a nationwide organization, it's a 7 worldwide organization and typically we strive for 8 consensus. And so I hear two sides and I would like 9 to see an effort to reach consensus. To reach 10 consensus you have typically all parties try to step 11 to the table and I really would like to know what you 12 think about this. 13 MR. ERLER: I think at least at the lower 14 group level because I did sit in on one of the groups 15 on fatigue analysis that we were reasonably close to 16 consensus and there were a couple of issues that were 17 apart on the staff and the industry on a level of 18 conservatism of these Fen factors. 19 With the current version, we changed the 20 basis for defining these factors to this 95/5 which 21 reduced some of the conservatism in the original staff 22 position. 23 So we believe we've moved towards the Fen 24 position that the industry was proposing at one time

• 25 and we were hoping that to NEAL R. GROSS see COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

a little bit of (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I, I I~ 131 1 movement at ASME to recognize-that one, we had moved 2 our position slightly to be slightly less conservative 3 and it shouldn't be that far away from what they were

  *4      at least proposing at the lower code committee levels.

5 DR. WALLIS: So they are proposing an Fen 6 approach? 7 MR. ERLER: They had an Fen approach that 8 was proposed. It never got through the lower 9 committee levels. 10 DR. WALLIS: On Slide A, they seemed to be 11 saying the Fen approach itself is no good. The 12 factors are not appropriate and inconsistent. 13 MR. ERLER: That's directed at the reg.

14 guide itself and the specific factors.

15 DR. WALLIS: But you're saying that the 16 F~ approach itself is no good? 17 MR. ERLER: No. 18 DR. WALLIS: I thought you were saying 19 that the whole approach is no good. 20 CHAIRMAN ARMIJO: I guess I am more 21 troubled by the fact that at this stage, there is 22 still wording in your chart that say there's a lack of 23 agreement on need to do anything. And I would that 24 means that some people in your committees are just

• 25 saying we don't have to do anything at all, period.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

[: I' 132 1 And somehow that's gotten past your hierarchy that 2 says sorry, guys, there is a need to do something, so 3 we're not going to put that bullet on there, but we're 4 going to do something. 5 At least I'd be a little more comfortable 6 with the ASME's position if they said hey, we 7 recognize there's a need to do something. The old

  ,8    codes and methodology and the old data wasn't just 9    perfect.       We have modern ways of doing things and 10     we're going to do it in a modern way and we'll work 11     with NRC to work it out.            That, to me, would be a more 12     comfortable 13                      MR. ENNIS:       That comes back to the focus 14     of coming to consensus on the need.                   What is the need 15     that you're trying to address?                  If the need is let's 16     use      more  modern     data     or    let's       use   more    modern 17     technique,      to upgrade ourselves,             that is satisfying 18     one need.

19 If you're saying the need is there are 20 fatigue failures of this type in plants and we have to 21 change -- 22 CHAIRMAN ARMIJO: I think this industry 23 has failed many times to design things properly with 24 respect to environment and we've cracked pipes and

• 25 replaced pipes and cracked numerous components, spent NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

133 1 billions of dollars and when *that happens everybody 2 agrees there's a need to do something. This approach says hey look, we've_ gotten 4 a lot smarter, we've got more data. We've got more 5 experience. So we can anticipate these things, design 6 it right, put the right criteria, maybe be more 7 flexible on the usage factors that the NRC regulates 8 because we know more. It seems to me that's 9 fundamentally a sounder way of approaching it and 10 rather than say well, let's wait and see if we get 11 some unexpected fatigue failures. I just don't like 12 that approach because that's what we've been doing for 13 so many years . 14 MR. BALKEY: And for our last slide here, 15 I guess we felt that -- you've heard through the 16 presentations that well, it's not explicitly, but we 17 do have factors that are considered in our design 18 criteria and we've obviously wrestled with the need to 19 change the current design requirements and if there is 20 the need, then how that change gets implemented. So 21 it's the aspect of in going back and -- 22 DR. WALLIS: It seems to me the need is to 23 respond to this new data which seems to be fairly 24 broad and not comprehensive which shows that you can

• 25 get fatigue failures earlier NEAL R. GROSS if COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

you have these (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

il 134 1 environments. 2 I think as I gather from this -- I mean 3 your position is that your factor of 20 is good enough 4 because these effects are not that big. Is that 5 really your basic position, that if the effects turn 6 out to be bigger, then it could be covered by your 7 factor of 2 0, then there would be a more obvious need. 8 Is that your position really, that the 20 covers this? 9 MR. ERLER: Basically, that is the 10 position of the various codes and subgroups that the 11 fact, everything has come to a vote. It's been 12 extremely towards the side of not changing it. 13 There's been new curves that have been proposed . 14 There's been an EPRI approach that's been proposed and 15 it ends up 16 DR. WALLIS: The rationale has been that 17 the factor of 20 covers this new 18 MR. ERLER: There's a whole series of 19 rationale. You've got to have -- 20 DR. WALLIS: Some of it could be just we 21 don't want to do anything. 22 MR. ERLER: No, no. I don't think that's 23 the truth of any of the working group. We've had two 24 task groups that have been assigned within Section 3

• 25 to work through it. The design group has been -- and NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

135 1 it's going to be Richard Barnes wasn't able to make it

  *2 here,       but he wants to drive it up to Section 3 and 3 make a decision with regard to get a vote at Section 4 3 and at such a vote you'll see the negative reasons.

5 They have to be writ ten reasons as to why -- as 6 opposed to discussions. 7 We have months and months of discussions 8 that last all day, arguing about the shape of these 9 curves, the data, the statistics. The experts are 10 quite amazed, you know, where they all come from, but 11 the process is such that I think that it is really a 12 series of concerns that have been identified of how to 13 deal with it. The simple statement that we agree the 14 phenomena is there. 15 To date, it looks like we haven't had any 16 failures that we can identify specifically with 17 environmental contributing to a shorter fatigue life 18 for a particular component provides a lot of 19 reassurance for people to -- at the same time, there 20 has not been an agreement to stop doing anything on 21 it. 22 I mean our last bullet down here is we're 23 going to continue to get money and do research, work 24 with the NRC, work with all of the organizations to

• 25 get data, to find out where it's appropriate.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

136 1 It's not ~nusua~, the design of any-- of 2 a building that you don't design for exact conditions 3 that you have. 4 DR. WALLIS: Does license renewal make a 5 difference? Now you're extending the life, so that 6 experience up to date with fatigue may not cover the

  '7 future.

8 DR. HOFFMAN: Can I? Well, this 9 environmental fatigue effect is addressed for license 10 renewal by a set of sample analyses. But, in fact, to 11 my knowledge, no plant that's gone for license renewal 12 has increased their number of transients by a factor 13 of 50 percent . 14 DR. WALLIS: It is close to this usage 15 factor limit? They don't get close to that? 16 DR. HOFFMAN: No. It's been addressed for 17 license renewal and it's just another example of a lot 18 of the extra margin that's built into the Section 3 19 design process. 20 The design transients that are identified 21 are far grater than what are actually seen in 22 operation. So there's lots of other sources of margin 23 in the design. 24 MR. FERRER: May I comment on that because

• 25 we have looked at at least two dozen plants on license NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

i* 137 1 renewal and actually we have a NUREG CR-6260 which we 2 did some sample analyses. The staff had done by EG&G 3 at Idaho. That's not quite correct. There are cases 4 where the number of design transients was 5 nonconservative and it occurred mostly on BWRs where 6 they originally assumed 120 cycles of start-up and 7 shut-down and now they're postulating something closer 8 to 200 cycles. 9 And so there are cases where there were 10 more design cycles, the original design was not 11 necessarily conservative in terms of cycles. There 12 are a number of cases that were evaluated where they 13 did an evaluation and the fatigue usage came out 14 greater than one. And there's an open issue for them 15 to come back before the period of extended operations 16 to propose to either do some more rigorous re-analysis 17 or to do some kind of an aging management program at 18 those locations. And that's an open issue in a number 19 of license renewal reviews. 20 DR. WALLIS: Now if you use the F factor 21 method as proposed, presumably those usage factors 22 would become even bigger. 23 MR. FERRER: Well, that's what we did in 24 license renewal .

• 25 DR. WALLIS: You did in license renewal.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. {202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com I'

I' 138 1 You used the F factor. 2 MR. FERRER: Yes, but we used a slightly 3 more conservative position than is now being proposed. 4 We originally took the 2 and 20 adjustment factors to 5 the environmental data to get the design curve. Now 6 we use this 95/5 which is 12. So it's not quite as 7 conservative. 8 CHAIRMAN ARMIJO: Did you have to relax 9 the regulatory position on the -- what was allowed, 10 the usage, the .1? 11 MR. FERRER: What we did in license 12 renewal was we didn't apply the environmental on the 13 calculation of the pipe postulation locations. We 14 only applied it on the calculation of the fatigue 15 usage for code compliance considerations. 16 The reason this hasn't been discussed 17 previously, I think is the first time the staff really 18 thought about it is based on the public comments to 19 the reg. guide. When somebody mentioned that this may 20 be a problem, causing additional pipe break 21 postulations, we said we' 11 consider adjusting the 22 criteria. But in license renewal, we've had no 23 problems with that because we didn't specifically ask 24 them to apply the environmental factors on a break

• 25 location calculation.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I. I. 139 1 DR. BONACA: Now these are Regulatory 2 Guide . This is an approach. You still have the 3 option of presenting alternatives. 4 MR. FERRER: You are correct. 5 DR. BONACA: That means there wi 11 be 6 additional work and maybe there is some consensus. 7 MR. BALKEY: That's what we're trying to 8 say in the last slide here. I mean it's we're not 9 trying to say we don't want to do this. We do, but 10 we're just wrestling wit how you do it and we're 11 willing to even look at the draft reg. guide as a code 12 case in order to get the input to the ASME 13 constituents . 14 We're also looking at other alternatives 15 and we have other alternatives in process. But it's 16 a difficult challenge with getting all the 17 stakeholders to agree, based on an extra day, how we 18 can go forward in doing that, both from both design as 19 well as in operational evaluation. 20 CHAIRMAN ARMIJO: Okay. 21 MR. BALKEY: Thank you. 22 DR. WALLIS: What do you expect the ACRS 23 to do? 24 DR. SIEBER: There's always somebody.

• 25 (Laughter.)

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005*3701 www .nealrgross.com

I, I. 140 1 DR. WALLIS: Are we supposed to come down 2 on some side or the other or are we supposed to say 3 knock your heads together and say go away and agree or 4 what are we supposed to do with this? 5 MR. BALKEY: The thing that struck me, as 6 I said, I did piping work in the 1970s for about 10 7 years and this issue became much more knowledgeable as 8 the reg. guide came out over the summer. 9 And one thing, I get concerned when we met 10 from B311 and it addressed the comment about we want 11 to go to much better analytical methods . We went 12 through B311 to 317. Everyone viewed 317 for better 13 design rules. The plant that I worked on, the 14 architect did all the piping layout based on 311. But 15 when the commitment was one that hey, this plant would 1,6 be licensed to the B317 code, then a confirmatory 17 analysis was done. 18 And what happened when we moved and did 19 this better work, we ended up adding in 230 snubbers 20 at the last couple months before this plant needed to 21 go on critical path. And I know when I went out to 22 walk down the line with the archi teet, I mean we 23 really had a lot of congestion. And you set yourself 24 up for pipe growth that ended up, you know, snubbers

• 25 would lock up and you end up with high stresses that NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

II 141

  *1    you weren't counting on. *

• 2 And as John Ferrer and my other colleagues 3 said then, that was just one plant. That was 4 experienced across a number of reactors back in the 5 '70s. The code worked real hard with the NRC. We 6 actually changed evaluation methods to pull all those 7 restraints back out. But snubbers as well as whip 8 restraints. That was an enormous amount of effort.

9 I think the question that I have from that 10 experience from 30 years ago is right now I've not i1 seen where somebody took a plant and did a trial 12 application to see using these methods from a design 13 standpoint. where do we end up here. 14 What we have to be careful is that we 15 don't end up what we did 30 years ago where you do a 16 lot of work and then you find out well, we're back 17 here again. We're revising this criteria, that 18 criteria and all it does is set up regulatory 19 instability, both with the code as well as the 20 regulations. 21 That would be -- that's the question in 22 terms, because the plants that we hope are all coming 23 forward, they're all looking for regulatory stability. 24 They're trying to keep the design fixed and not get

• 25 into what we did 30 some years ago.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I! 142 1 So that would be* the question I would have 2 with and I know you've done this on other 3 regulatory guides where instead of the issue is final, 4 it's issued out as a trial application until you get 5 real experience, then make the determination. 6 A trial application would be real helpful 7 data to ASME. 8 DR. WALLIS: Would that fit in with your 9 second bullet here? I'm not sure what the code case 10 is. 11 MR. BALKEY: A code case allows 12 whenever we have a new technology and you want to try 13 it out, a code case allows for early use and gets some 14 trial applications. A good example is -- 15 DR. WALLIS: It doesn't make a lot of 16 sense. Does the NRC agree with that sort of thing? 17 MR. SIEBER: They occasionally approve it. 18 MR. FERRER: Yes, as a matter of fact, one 19 of the proposals in the ASME was exactly to do that 20 and it was with the Fen approach, but it didn't go 21 through the system. 22 We would have probably -- had they put one 23 out, we would have probably endorsed it with some 24 exceptions, minor exceptions. We would have been

• 25 slight more conservative, but we would have endorsed NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com I.

143 1 it and I said that at many of the code meetings that 2 I sat in when they were discussing that there was a 3 difference between ASME and NRC that all they had to 4 do was issue their proposal and we would adopt it with 5 the exceptions that we thought were necessary. 6 MS. VALENTINE: And I would just like to 7 add to that, this is really a timing issue. As we 8 said many times before there has been discussion on 9 this for many, many years. 10 The staff is very clear with the 11 instruction from the Commission that we have several 12 high priority reg. guides to issue by March 2007 to 13 support new reactor applications. As we stated many 14 times, this has been a consistent process, but this 15 does not our reg. guide does not stop that 16 consensus process. 17 This is a Regulatory Guide, not a 18 regulation. So the staff has been very clear on what 19 we expect to come out of this meeting which is 20 agreement for issuance of an effective reg. guide. 21 CHAIRMAN ARMIJO: Okay, with that, I think 22 we'll close on this one. We have one more 23 presentation by thank you, gentlemen, for your 24 presentation. I appreciate it .

• 25 (Pause.)

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com i.

I, I 144 1 CHAIRMAN ARMIJO:' Okay, let's start. 2 MR. COFFLIN: Mr. Chairman, Committee 3 Members, first of all, I'd like to thank you for 4 giving me the opportunity to make s ta temen t here 5 today. I won't be presenting. I'll just be taking 6 from some notes I have. 7 I kind of got inserted at the last minute 8 and I appreciate that. 9 Thank you, Gary. 10 My name is David Cofflin, and I work for 11 AREVA MP, Incorporated in Lynchburg, Virginia. I 12 supervise a group of engineers who are responsible for 13 loading, stress and fatigue analysis of the reactor 14 coolant system for the USEPR which is AREVA's entry 15 into the advanced light water reactor market. And as 16 such, I have a practical viewpoint of what this reg. 17 guide means to people say at the working level. 18 We have received DG-1144 some time ago and 19 we issued it to all three regions of AREVA. That 20 would be France and Germany and the U.S. And we 21 reviewed in September on the 22nd. We sent a letter 22 to the NRC which outlined out concerns and comments 23 with the draft reg. guide. 24 I actually have copies of the letter here .

• 25 There were some passed out earlier.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. Does everyone (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

145 have one? * * ..J' Others in the gallery, I have some here too. My purpose here today is not to go through the letter point by point or in detail. I just want to summarize our major areas of concern with the draft reg. guide. What AREVA would like out of this is that the advisory committee consider these concerns and questions when they're formulating their recommendation to the Commission regarding implementation of the draft reg. guide. I' 11 move onto our concerns. AREVA is not aware of any operating experience that supports the need for the conservative fatigue design rules proposed in DG-1144. I guess my placement in the schedule was fortunate because ASME has handled most, if not all of these comments already. DR. WALLIS: Are you saying that because nothing has happened we don't nearly need a rationale way to predict what might happen? MR. COFFLIN: I would argue that the method that we're using now is sufficient for what we're doing .

• DR. WALLIS:

NEAL R. GROSS We don't need a COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. rational (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

II I 146 1 method of predicting what might happen? 2 MR. COFFLIN: That's a fair statement.

  *3    But all I'm saying is I think the method that we have 4    now is rational.

5 DR. WALLIS: But it seems to be the 6 argument that because nothing has happened so far, we 7 don' t have to worry about it . We don' t need to 8 rationally predict what might happen? 9 CHAIRMAN ARMIJO: If absolutely nothing 10 changed. And the methods and the data and the 11 regulations of 1960 or whatever, then you might have 12 an argument . But things are always changing and I 13 don't know if we can count on that kind of stability 14 in the analytical processes to be there to provide the 15 conservatism that it provided by being just so 16 simplistic. 17 And so I don't understand this idea that 18 we have to have something fail before we do something. 19 MR. SIEBER: Let's not think that nothing 20 has ever failed. There's been a lot of nickel-based 21 alloys that have not performed well. 22 MR. COFFLIN: Through different 23 mechanisms. 24 MR. BANERJEE: Every 7 or 10 years we find

• 25 a surprise. Is that Bill Shack who said that?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

    )1 i'

147 1 (Laughter.) 2 MR. SIEBER: And that keeps a lot of us 3 employed. 4 CHAIRMAN ARMIJO: Okay, go on. 5 MR. COFFLIN: AREVA believes that the 6 proposed rules and we've been through this again, will 7 lead to more postulated break locations which will 8 lead to more whip restraints and jet shields. 9 This will lead, in turn, to reduction in 10 overall plant safety due to the increased risk of our 11 spring thermal expansion and more difficulty in 12 obtaining accurate inspection results due to the 13 addition of whip restraints and jet shields. Again, 14 a point that the ASME has made. 15 It is not clear why the application of the 16 proposed rules is not limited to those locations which 17 are most sensitive to environmental fatigue effects 18 similar to how environmental fatigue effects are 19 treated in license renewals phase. License renewal is 20 operating under a different set of rules. 21 AREVA does not believe that the NRC should 22 establish very conservative design rules without peer 23 consensus which we talked about. 24 The entire fatigue analysis methodology

• 25 should be considered when developing rules to account NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com I!

i 148 1 for the effects of environment,_* rather than limiting 2 considering to material effects only. And practiced 3 the current ASME fatigue analysis and practice the 4 current ASME fatigue analysis methodology already 5 contains multiple conservatisms that are not easily 6 removed from the fatigue analysis process. 7 Finally, in our September 22nd letter 8 through the NRC, AREVA has highlighted several 9 technical concerns with the proposed rules. These 10 include concerns with the representative nature of the 11 materials tested and the loading applied during the 1,2 tests. The difficulty in translating results from 13 laboratory specimen test results to field components 14 and the lack of appropriate threshold values in some 15 of the formulations. 16 And that is a very quick and brief summary 17 of what's in the letter. You'll find much more detail 18 in the letter. I'm a practical guy. I'm trying to 19 look at it from the standpoint of what it means to me 20 as a piping and component analyst, but particularly 21 the technical component, the technical corrunents. 22 There's a fair bit of detail and background in the 23 letter that describes what they are. I just briefly 24 hit them .

• 25 Thank you.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

149 1 DR. WALLIS: You.seem to agree that there 2 is an environmental effect.

 -3                     MR. COFFLIN:         Yes, sir.         There is.

4 DR. WALLIS: But it's not big enough to 5 require any change in the procedures. 6 MR. COFFLIN: I believe to restate that is

  .'7 that it -- we believe that the methods that we're 8 currently using would             cover      environmental         fatigue 9 effects.

10 MR. BANERJEE: Your letter here has quite 11 a lot of detail technical points. 12 MR. COFFLIN: Yes, sir. 13 MR. BANERJEE: The NRC, presumably, has 14 looked at this because the letter was sent on the 22nd 15 of September. And did you respond to these points 16 that they made? 17 MR. COFFLIN: I think one of the biggest 18 points that they made and said previously that it may 19 increase the number of pipe break postulations and we 20 considered that a valid comments and would consider 21 adding the criteria. 22 With regard to some of the detailed 23 technical comments on the conservatisms and the 24 analysis, we agreed with some of them, but some of

• 25 them we disagree with and NEAL R. GROSS one COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

of them we just (202} 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I~

    'I 150 1    mentioned         earlier      in    the     number       of   postulated 2    transients is not always conservative as we found in 3    our reevaluations.              There' s     some that they under-4    estimated in the original design and it turned out to 5    be more transients than they estimated.

6 One of the comments in the AREVA letter 7 was technically incorrect. One of the arguments they 8 made in the letter was that the ASME evaluation 9 criteria is based on Tresca which is called the 10 maximum stress criteria and that was overly 11 conservative in the analysis. i2 Well, the Tresca criteria is an overly 13 conservative failure criteria, but if you use a 14 different criteria such as VonMises criteria, you 15 would calculate a higher stress and therefore a higher 16 strain to go into the ASME fatigue curves. So really 17 that argument, that part of it is really not 18 conservative, if you look at it in terms of VonMises 19 criteria. 20 MR. GURDAL: But Omnesis is less. I hope 21 it is so. I may not speak, but it is truth. In every 22 book they list a rectangle, and an ellipse and it 23 shows that you can go to a higher stress level to come 24 to a rupture when you have Omnesis. So in other

• 25 words, the Omnesis stress itself is less than Tresca.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com I

    ,I

f* 151 1 Tresca is always more severe than Omnesis. All the 2 same. All the same. Fifteen percent maximum. I'll 3 send you that page. 4 MR. FERRER: I' 11 refer you to an MRP 5 study where they were looking at those U-bend

  .6    specimens         that    Dr. Chopra      showed       you   and      they 7    evaluated them based on Tresca and showed that there 8    was a clear effect of the environment.                      And they went 9    back to a VonMises type criteria and showed that with 10     higher calculated strains they were closer to the ASME 11     fatigue curves.          However, you don't use VonMises to do 12     fatigue analysis.

13 MR. GURDAL: This is not a competition for 14 Omnesis and Tresca. It's the one where it's called 15 maximum total principle strain range. It's that one. 16 It's not a comparison between Tresca and Omnesis. 17 MR. FERRER: I don't think we're going to 18 get anywhere with this cross argument, but if you go 19 into a textbook, they will show you a plot of VonMises 20 versus Tresca. It's a standard plot under two 21 dimensions. 22 MR. BANERJEE: To go back to the original 23 question, they lay out a number of let's say technical 24 comments. Now do we have a response to these -- okay .

• 25 That's really the question I was asking.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

Ii

    'I 152 1                       And   then* **these       ~responses        have       been 2    received by AREVA, presumably.

3 MR. GURDAL: No. 4 MR. BANERJEE: Have not. I see. I think 5 that answers my question. 6 DR. SIEBER: Or by us. 7 MR. BANERJEE: Or by us, right. 8 DR. WALLIS: We have received them. 9 DR. SIEBER: We have? 10 MR. SANTOS: It's on the disk. 11 DR. SIEBER: Oh, okay. I'll look at this. 12 CHAIRMAN ARMIJO: But I think this thing 13 about pipe whip restraints and snubbers and 14 proliferation of those things as being the only 15 outcome of applying this reg. guide is kind of hard to 16 believe. It's either that or spend some more money 17 and more sophisticated mechanical analysis and/or seek 18 some relaxation of the criteria, all of which are 19 available to you. 20 I don't think it's the end of the world 21 and the only thing that will come out of this.is a 22 bonanza from the pipe whip restraint industry: It 23 seems like that's the point that's getting overstated, 24 at least my point .

• 25 DR. SIEBER: I guess I'm in a position to NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

II 1: 153 1 confirm that having to redo~your analysis and have a 2 ton of restraints costs millions of dollars, does "3 occur. 4 CHAIRMAN ARMIJO: But I think this is a

  *5    different situation now, Jack.                     They're saying that 6    nobody wants it.             The staff certainly doesn't want 7    that to be the outcome,                at least that's what I've 8    heard.

9 DR. SIEBER: Well, you may be in better 10 shape now than you were in 1980 when these things 11 became a fact. 12 DR. WALLIS: I don' t quite understand 13 that . Because if the F factors are already within 14 this ASME factor of 20 as they claim, I don't see why 15 it's making that much difference. 16 DR. BONACA: Well, that is the point of 17 ASME. I think the presentation we got from the staff 18 made a case for addressing specifically environmental 19 concerns and so now if, in fact, this causes many more 20 restraints to be placed in location and an assumption 21 to be made, does it mean that the ASME position, in 22 act, does not address environmental concerns 23 adequately. We're left with a question. It means 24 that there is sufficient difference there to state

• 25 that the ASME case currently NEAL R. GROSS does COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

not address (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I' I'

                                                                             . 154 1    adequately the environmental*concerns, it seems to me.

2 If you're telling me that there are going 3 to be hundreds of additional constraints and locations 4 for breaks, it means to me again that there is 5 significant difference between what we have heard in 6 a technical presentation where environmental concerns 7 were specifically addressed in the ASME case which is 8 really most about the basis. It simply provides some 9 multipliers. 10 So I'm left with having to judge between 11 something I understand. I saw a presentation. I saw 12 some basis for it versus an assumption that says this 13 number has not been causing problems in the past, so 14 we just live by that. 15 I really have the feeling that I don't 16 know, maybe it's not going to cause so many additional 17 restraints. 18 DR. SIEBER: It seems to me that if the 19 staff were to issue this reg. guide and ASME would 20 develop their code case and staff would approve that 21 with some delayed implementation, we would learn a lot 22 of these answers. 23 DR. BONACA: Yes. 24 DR. SIEBER: Technically that's -- if we

• 25 say don't issue the reg. guide, it will be 25 years NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com I,

I' I' 155 1 that won' t happen. On* the other hand, industry 2 arguments are good enough as to question whether this 3 is too rigorous. I think this is a way to show 4 whether it is rigorous or not, too rigorous or not. 5 DR. BONACA: You know, I agree with you, 6 by the way, on the case. On the other hand, this is 7 the first time I've seen specific calculations or 8 tests addressing environmental concerns. We have 9 discussed this through license renewals plenty of 10 times and we had no information except we had GSI-190 11 and we were left with the question of what does it 12 mean for license renewal 20 more years? This is the 13 first time I've seen some of these . 14 Now the letter from AREVA questions some 15 of the technical aspects of the tests, so that-- it's 16 open here and I think there are answers for that. But 17 in general, I think that we have seen some technical 18 basis for what is being proposed. 19 DR. SIEBER: I think what the staff is now 20 doing in license renewal space is probably as good as 21 they can do with the regulatory authority that they 22 have. 23 Yes sir? 24 MR. ERLER: I guess the one other issue

• 25 that you've identified NEAL R. GROSS the COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

issues that are (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

156 1 critical. I'd add to that how to apply the Fen* That 2 is a difficulty . It was identified in the MRP-47 and 3 that has not been addressed. There's as many 4 negatives on getting something through, of passing 5 something that you don't know how to apply it to the 6 person. So that's what's going to take us a little 7 more time in our code case to be able to develop the 8 application of it so that it makes sense, with the

  *g     code equations and everything.

10 That's why we really would like to buy 11 some time. I think it' s good that you put some 12 pressure on us to move by having something in front, 13 but I would like rather than lock it in place, some 14 time there to work through that. 15 DR. SIEBER: There is a way to do that, I 16 think. 17 MR. FERRER: Again, we need something to 18 implement our current reviews. If ASME develops 19 something as has been stated here before, this is a 20 regulatory guide, just gives a method acceptable to 21 the staff and an alternative method could be found 22 acceptable if we find you put out something that had 23 an adequate basis to cover the concerns. 24 MR. BANERJEE: How many reviews are you

• 25 facing in the near future?

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234*4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

     ; i

I;I' 157 1 MR. FERRER: '*Right *now, two. We have 2 ASBWR and EPR. That's why AREVA is here. The other 3 -----one would be GE. And they're near term. We need the 4 criteria now if we're going to implement something. 5 DR. WALLIS: We have no idea what is the 6 actual impact of these criteria on say the ASBWR? 7 MR. FERRER: No, because at this point, 8 this was an open issue in the review and we're waiting 9 for the proposed response on how they're going to 10 address it. Because at the time we raised it, they 11 didn't-- the reg. guide wasn't on the street. In the 12 interim, it has now been issued, so that they could

 ~3           come in an propose to use our reg. guide and then we 14           could do an evaluation of its impact.

15 DR. KRESS: Won't it show up at the COL 16 stage instead of 17 DR. SIEBER: Yes, but that's 18 certification. It will be grandfathered. 19 DR. BONACA: It will show up at the design 20 stage. 21 MR. FERRER: This is not quite true 22 because they are doing some sample analysis in the 23 design certification stage for both plants, I believe, 24 and so we will get a feel for the amount, whatever the

• 25 amount they do in the design certification stages, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

I 158 1 what the impact is.

2 DR. SIEBER: Well, it certainly is easier 3 to do before you've taken any mortar and steel and 4 played with it. Pencil and paper is far cheaper. 5 MR. BANERJEE: Well, with EPR you still 6 have time before that happens, right? 7 MR. FERRER: Yes, yes. Right now they

  '8    have a topical in I think on the criteria which we're 9    going to review.           We haven't really gotten started 10     with       it  yet. ESBWR,     we're      much     further      along.

11 They're actually doing analyses of certain systems and 12 we have the issue as an open issue with them, waiting 13 to see how they're going to attempt to resolve it.* 14 If we can't resolve it in the design 15 certification review, then it will be an open issue 16 and it will roll over to COL. 17 DR. BONACA: Now AREVA is in the process 18 of building an EPR in Finland, correct? 19 MR. FERRER: That's correct. 20 DR. BONACA: So you should have some 21 feedback there. I mean what kind of codes and 22 standards are they using? 23 MR. COFFLIN: They are using RCCM which is 24 the French code. It's roughly equivalent to the ASME .

• 25 It does not have environmental fatigue rules in it.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

159 1 DR. SIEBER: Then that' s not going to help 2 you . 3 MR. GURDAL: I am Robert Gurdal . For 4 Finland, like David said, they are using RCCM which is 5 the code from the French which was really based on the 6 ASME to start with, but then it just further 7 developed, so it's kind of a hybrid from the ASME. I 8 don't know how to say. But now that code does not 9 tell you to do environmental effect, but STUK, if you 10 know them, S-T-U-K, that's like the corresponding NRC 11 in Finland, can I say like that, I think. 12 DR. SIEBER: Right. i3 MR. GURDAL: And their code is called YVL . 14 They are asking what the French, because it's really 15 under France and Germany, are going to do for the 16 environmental effects. So it's a question there, but 17 it's kind of kept open to the French to see what they 18 want to do. And what they have promised is to look at 19 four locations very similar to the license renewal and 20 those four locations are surge, surge nozzle and CDCS 21 with a nozzle. What is it? Control and volume? 22 DR. BONACA: So AREVA has an ability to 23 have a test then, it's an evaluation in and of itself; 24 MR. GURDAL: Yes.

• 25 DR. BONACA: This case, NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

and really see (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

II 160 1 what the impact is. 2 MR. FERRER: It may be a timing thing. I 3 prefer the music. 4 MR. GURDAL: They hope to do this analysis 5 for the first three months of 2007, but then prior to 6 that they are also doing tests, because what they

  *7    don't really believe in is those triangular types of 8    cycles.        They say that the real cycles are more what 9    I    would call Delta T1,            Delta T2         types. In other 10     words, when the fluid is coming.                  So in that case, the 11     environmental effects are in place.                       But the other 12     big, big thing that they don't believe is that you 13     don't have the surface effect and the environmental 14     effects at the same time.               Very important.

15 He has an incredible surface effect in his 16 12 which is what between 2 and 3.5. You take the 17 square root of that, that's approximately 2.6 and the 18 surface effect we see is something like 1.1, 1.2 that 19 you can see in the EPRI tests done in Ireland. 20 So what they really think is that once you 21 use the environmental effects, you should not have 22 those factors of 2 and 20. If you have any factor a 23 lot less of 2 and 12, and that's completely 24 consistent with the Japanese who have a 1.5 down and

• 25 nothing else. First, that's Dr. Nakamura if you want.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

II II I 161 1 DR. WALLIS: That's in your letter, right? 2 MR. GURDAL: I don't remember. That was 3 in September. 4 Part of it is. I could in the 5 meantime, we learn a little more, but because of the 6 deadline we have to rush. That's why it's September 7 22nd, which was a Friday for the 25th. We would have 8 more information. And the French, I spoke with the 9 French yesterday on the phone and he wants to be sure 10 for Flamonville, that's the second EPR in the world, 11 the third, hopefully, is in the United States. For 12 Flamonville, it's already decided no environmental 13 effects. And that's reported by EDF. 14 No, the environmental effects is an R&D 15 phenomenon that you don't see in components. That's 16 his one sentence. Maybe we shouldn't put that in the 17 record. 18 So Flamonville the only interesting 19 question about Flamonville is they are discussing 20 whether the design would be according to ASME or RCCM. 21 I don't know if that -- but for Finland, it's RCCM. 22 Oh, but the fatigue curves in the RCCM are the same as 23 ours, the fatigue curves. 24 CHAIRMAN ARMIJO: Okay, thank you very

• 25 much.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www .nealrgross.com

I' I: 162 1 MR. FERRER: Thank you. Thank you for 2 your*time. 3 CHAIRMAN ARMIJO: I think we've got -- 4 we're done, unless the Committee wants to make any 5 comments, speeches. There will be an abridged

  *6    presentation to the Full Committee.

7 DR. WALLIS: Do you want to have a caucus 8 of the Committee off the record, after this? 9 CHAIRMAN ARMIJO: Yes, I would. I think 10 it would be a good idea of what to write. 11 Okay, with that, I'm going to close the 12 meeting and thank everybody for their presentations 13 and for the discussion. I think it was very well 14 done. Off the record. 15 (Whereupon, at 5:18p.m., the meeting was 16 concluded.) 17 18 19 20 21 22 23 24

• 25 NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W.

(202} 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

• CERTIFICATE This is to certify that the attached proceedings before the United States Nuclear Regulatory Commission in the matter of:

Name of Proceeding: Advisory Committee on Reactor Safeguards Subcommittee on Materials, Metallurgy and Reactor Fuels Docket Number: n/a Location: Rockville, MD were held as herein appears, and that this is the original transcript thereof for the file of the United States Nuclear Regulatory Commission taken by me and, thereafter reduced to typewriting by me or under the direction of the court reporting company, and that the transcript is a true and accurate record of the foregoing proceedings.

                                ~rz:~~

Eric Hendr£xson Official Reporter

• Neal R. Gross & Co., Inc.

NEAL R. GROSS COURT REPORTERS AND TRANSCRIBERS 1323 RHODE ISLAND AVE., N.W. (202) 234-4433 WASHINGTON, D.C. 20005-3701 www.nealrgross.com

.-----~*,::-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - . , RG 1.207

• GUIDELINES FOR EVALUATING FATIGUE ANALYSES INCORPORATING THE LIFE REDUCTION OF METAL COMPONENTS DUE TO THE EFFECTS OF THE LIGHT-WATER REACTOR ENVIRONMENT FOR NEW REACTORS Hipolito J. Gonzalez Corrosion and Metallurgy Branch Division of Fuel, Engineering and Radiological Research Office of Nuclear Regulatory Research (301) 415-0068 hjg@nrc.gov Omesh K. Chopra Nuclear Engineering Division Argonne National Laboratory (630) 252-5117 okc@anl.gov Presented to Advisory Committee on Reactor Safeguards Subcommittee on Materials, Metallurgy, and Reactor Fuels Rockville, Maryland December 6, 2006 Agenda
• Discuss RG 1.207

             -Historical Perspective
             -Overview ofRG 1.207
             -Technical basis, NUREG/CR-6909 Rev. 1
             ~Regulatory Positions

• Resolution of public comments on DG-1144 and draft NUREG/CR-6909 2

Environmental Effects on Fatigue Life: Historical Perspective

• ASME Section III fatigue design curves developed in the late 1960s and early 1970s

    - Air environments at ambient temperatures
    - Adjustment factors of 2 on strain and 20 on cyclic life

• Studies in Japan (Higuchi & Iida, 1991) and those at ANL (NUREG/CR-4667, 1990)- potentially significant effects of L WR coolant environment on fatigue life of steels 3

Environmental Effects on Fatigue Life: Historical Perspective (cont.)

• Since late 1980s, NRC staff have been involved in discussions with ASME Code committees, PVRC, and technical community to address issues related to environmental effects on fatigue
• 1991, ASME BNCS requested the PVRC to examine worldwide fatigue strain vs. life data and develop recommendations
• 1995, resolution of GSI -166 established that

    - Risk to core damage from fatigue failure of RCS very small; no action required for current plant design life of 40 years
    - NRC staff concluded that fatigue issues should be evaluated for extended period of operation for license renewal (under GSI-190) 4

Environmental Effects on Fatigue Life: Historical Perspective (cont.)

• In 1999, GSI-190, "Fatigue Evaluation ofMetal Components for 60-Year Plant Life" *

     ,--- 10 CFR 54.21, Aging Management Programs for license renewal should address component fatigue including the effects of coolant environment

• December 1, 1999, by letter to the Chairman of the ASME
• BNCS, the NRC requested ASME to revise the Code to include environmental effects in the fatigue design of components 5

Environmental Effects on Fatigue Life: Historical Perspective (cont.)

• ASME initiated the PVRC Steering Committee on Cyclic Life and Environmental Effects
• PVRC recommended revising the Code design fatigue curves (WRC bulletin 487)
• After more than 25 years of deliberation, no consensus has been reached 6

Environmental Effects on Fatigue Life: Historical Perspective (cont.)

• NRR User Need Request 2005-004 (January 7, 2005):

   - Develop guidance for determining the acceptable fatigue life of ASME pressure boundary components, with consideration of the LWR environment
   - For use in supporting reviews of applications that the agency expects to receive for new reactors.
   - Industry immediately notified

• High priority RG to be completed by March 2007 7

Environmental Effects on Fatigue Life: Historical Perspective (cont.)

• February and August 2006- NRC staff and ANL presented at the ASME Code meetings the technical basis draft NUREG/CR-6909
• July 24, 2006- DG-1144 and draft NUREG/CR-6909 published for public comments (60 day comment period)
• July 25, 2006- ASME PVP Conference, ANL presented paper on technical basis
• Public comment period ended September 25, 2006 8

Overview of RG 1.207 - Guidelines for

. Evaluating Fatigue Analyses Incorporating the
*Life Reduction of Metal Components Due to the Effects of the LWR Environment for New Reactors 9

How RG 1.207 relates to the Regulatory Requirements

• General Design Criterion 1

      - Safety related SSC must be designed, fabricated, erected, and tested to qualitY. standards commensurate with the importance of the safety function performed

• General Design Criterion 30

      - Components included in the reactor pressure boundary must be desi_gned, fabricated, erected, and tested to the highest practical quality standards

• 10 CFR 50.55a (c), endorses ASME BPV Code for design of safety-related systems and components (Class 1)

      - ASME BPV Code Section III, includes fatigue design curves

• Fatigue des.ign curves do not address the impact of the reactor coolant system environment 10

Objective and Implementation Objective

• To provide 'guidance for determining the acceptable fatigue life of ASME pressure boundary components, considering the LWR environment

    - Major structural materials: carbon steels, low-alloy steels, austenitic stainless steels, and Ni-Cr-Fe alloys (e.g., Alloy 600 and 690)

• Describes an approach that the NRC staff considers acceptable to support reviews of applications for new reactors Implementation
• Applies to New Plants
• No Backfitting is intended (conservatism on current reactors)
• Regulatory guides are not substitutes for regulations, and compliance with regulatory guides is not required.

11 How the Technical Basis was Developed 12

Technical Basis Report: NUREG/CR-6909 Rev. 1 - Effect of LWR Coolant Environment on Fatigue Life of Reactor Materials Omesh K. Chopra Nuclear Engineering Division Argonne National Laboratory 13 Issue - Environmental Effects on Fatigue Life

• Fatigue data indicate significant effects of LWR environment
• Data are consistent with each other & with much larger database for fatigue crack growth (da/dN)

    - in LWR environments, effects of material, loading, and environmental parameters are similar for fatigue £- N & CGR data

• £-N data have been evaluated to

    - identify key parameters that influence fatigue life, &
    - define range for these parameters where environmental effects are significant, i.e., establish threshold & saturation values

• If these conditions exist during reactor operation, environmental effects will be significant & must be addressed

    - subsection NB-3121 recognizes that the data used to develop the fatigue design curves did not include tests in environments that might accelerate fatigue failure 14

Fatigue Life

• Code fatigue design curves based on tests to failure of specimens; intent however is to avoid initiation of fatigue cracks
• Current test practice generally defines life of specimens as cycles to 25% load drop; typically this corresponds to a ~3 mm crack
• Surface cracks :::::10 Jlm deep form early during fatigue loading t

j_ Mechamcally Small Crack (Stage II TenSile Crack:

• Most of fatigue life associated with growth of cracks; 10 to 3000 Jlm
• Represented by two stages:

Initiation: microstructurally small Microstructurally cracks,< 300 !J.m A Small Crack (MSC) (Stage I Shear Crack) Propagation: mechanically small cracks 300-3000 Jlm (EPFM) 0 0.2 0.4 0.6 0.8 Life F raction 15 Fatigue Crack Initiation in Smooth Specimens j Mechanically 102 A533 Gr. 8 LowAIIoy Steel 2sa*c

                                           . Small Crack                              Strain Ran g e: 0.80%
                                           !~                                         Strain Rate: 0.004%/ s I
                              ~i                                     '

z Microstructural!~ , , Acr3

                    ~      Small Crack     ;    ,/           :'
                           ~               i/'            :'         l>a2
                           --- **--- -;             .....                            0.22 ,,m1 cydo        G""
                                 '         i     ..             601                  0.033 j.lmf cyc.se Linear-elastic or elastic.ptastic
                                                                                                  - 0 . . PVIR fracture mechanics 10*               - - (t- -- HighQiSSOIYed Oxygen Wiler
                                                                                                  * * -+- -- Hig h Gissolved Oll: yg en W.ter
                                                                                                  --6-- Air 100                     1000 Crack Depth Crack Leng th    ~m )

Environment affects both stages : initiation & propagation Effects on fracture mechanics controlled-growth are widely recognized E-N data indicate effects on growth of microstructurally small cracks may be even greater 16

ASME Code Fatigue Design Curves

• Code design curves based on data obtained on small, smooth specimens in R T air under constant loading conditions

      -   obtained under strain controlled, fully-reversed loading (R = -1)

• To use small-specimen data for reactor components, best-fit curves must be adjusted to cover effects of variables that influence fatigue life but were not investigated in the data

      -   such variables include mean stress, surface finish, size, & loading history. Data scatter & material variability must also be addressed

• To obtairi Code design curves the best-fit curves were

      -   first adjusted for effects of mean stress on fatigue life then reduced by factor of 2 on stress or 20 on life to account for other variables, but not an aggressive environment 17 Environmental Effects on Carbon & Low-Alloy Steels

• The effects of critical parameters on fatigue life:

Steel type: effects identical for carbon & low-alloy steels Strain amp: strain threshold near fatigue limit; no effect below threshold Strain rate: logarithmic decrease in life below 1%/s, saturation at 0.001 %/s; moderate effects above 1%/s Temperature: linear decrease in life above 150°C; moderate effects below 150°C Dissolved Oxygen: logarithmic decrease in life above 0.04 ppm, saturation at 0.5 ppm; moderate effects below 0.04 ppm Sulfur: effects increase with increasing S level, saturation at 0.015 wt.% Surface roughness: life of rough specimens is decreased in air; in high-DO water, surface roughness has little or no effect on fatigue life Flow rate: in high-DO water, effects decrease with increasing flow rate 18

Environmental Effects on Austenitic Stainless Steels

• The effects of critical parameters on fatigue life:

Steel type: effects identical for wrought & cast austenitic stainless steels Strain amp : threshold near fatigue limit; no effect below threshold Strain rate: logarithmic decrease in life below 0.4%/s, saturation at 0.0004%/s; moderate effects above 0.4%/s Temperature: linear decrease in life above 150°C; moderate effects below 150°C Dissolved Oxygen: in high-DO, effect may be lower for some steels; in low-DO, effect significant for all steels & heat treat conditions; Surface roughness: life of rough specimens decreased in air & low- DO water Flow rate: no effect of flow rate on fatigue life in high-purity water 19 Effect of Strain Rate A 106-Gr k Carbon St~el 104 , 2aa*c. '* -o.4% _t---t---+-~ 0 Alr + - --,j 0 A" + - -__,j

                                      ¢ S1mulated PWR                                             0 Simulated PNR 6 o0.7 ppm DO                                                 -o.7ppm00
                                 .. 1     .. 1                                               .. 1 6    ,.(

10-5 10-3 10-2 10-1 10-5 10*3 Strain Rate (%/s) Strain Rate (%/s)

• Little or no effect of strain rate in air & PWR or HWC BWR
• In high-DO, life decreases with decreasing strain rate below 1%/s, effect saturates at ;:::Q.OOI %/s 20

Type 316 SS, 325"C Strain Range lit = 1.2% DO = 0.005 ppm 0 0 Fraction of strain at slow rate: 0.170 0 Ill ~ ~ 1\ (\ 1\ ~ 0

                                                                                                                                                            ~          I Threshold Strain 1o2 .....................L...I..........,....L....I....I....J'-'-'-'-........_-'-'-....._.

0 .0 0.2 0 .4 0 .6 0 .8 1.0

                                                                ~** ,I&

• Data indicate threshold strain amplitude slightly above fatigue limit
• Tests with variable strain rate indicate that relative damage due to slow strain rate occurs only after the strain exceeds a threshold value 21 Effect of Dissolved Oxygen 104 A333-6 Steei 2aa* c Strain Amplitude: 0.6%

104 .-- 288"C, <8 ooQ.4% _ + - - - t - - - - - t - --,t 3 ~ 0 Strain ~ate (%/s) 0.004 (0.012% S)

                                                    ~                      0 e
                                                                                                      ~                                                                  0   A;r+ - -----,j
              !:;      0.01 (0.015% S) 0   S1mulated PWR 102 :--    0         0.002 (0.012% S) oiJ.7 ppm DO
                        .I                                                                                                                                          ,J   !:;
                                                                                                                                                                                 .J 10-3                                                                                                                                                            10-2 Dissolved Oxygen (ppm)                                                                                                Strain Rate (%/s)

• Life decreases above 0.04 ppm; effect saturates at ::::::0_5 ppm
• Moderate environmental effects in PWR or HWC BWR environment 22

Effect of Dissolved Oxygen Type 304 SS (Heat 30956) 288"C Open Symbols: <0.005 ppm DO Closed Symbols: -o.7 ppm DO 1~ L-wu~~wu~L-wu~L-wu~L-~~ 1~ 1~ 1~ 1~ 1~ 1~ Strain Rate (%/s) Strain Rate (%/s)

• Env. effects may be less in high-DO than low-DO water

     - for SA 304 SS, no effect of strain rate in high-DO water; for sensitized SS, strain rate effects same in high- & low-DO water
     - for low-C 316NG, smaller effect in high-DO than low-DO water 23 Effect of Material Heat Treatment Type 304 Stainless Steel 289"C
                                        - ---- - ---- 2 ------ - --- -~

gf 104

                           ~
                           ~

Q)

                           ~"         *******-*****ts*--*~  --~  __,__:A,_ __.,.==~

u.. 0 Strain amplitude -o.38% - * &~ ~ Air Saw-tooth waveform ----+--- BWR Strain Rate 0.004%fs tensile ****&*** PWR 0.4%/s compressive 0 5 10 15 20 25 30 35 EPR (C/cnl)

• In air & PWR water, heat treatment has little or no effect on life
• In high-DO water, fatigue life decreases with increasing degree of sensitization 24

Effect of Temperature A333-Gr 6 Carbon Steel A333-Gr 6 Carbon Steel 1()4 ~ *** 0.6%, 5

• 0.012 wt.%.- - + - - - + - - - + - --:1 1o4 ~ *** 0.6%, 5. 0.015 wt.%--1---1-- --::1

                                                                                                                    ~             -*--

Strain Rate

• 0.01%/s

                                                                                                                   ~                                                ~ ~- !- -* *
        ~                                                                                                                              0                                                       ..
        ~ 1o3 b---'~F==~=~                            -- '""-'-'-'
                                                               " f.'-"-- '" "-'"-'    .. "
                                                                                " -'f>-'-'----ol4    ..----:l
                                                                                              ' o. .-'-'           -; 103 ~-t------'~--.:!r---....::::..~-t--t---:1 t

u. 0 Straln~ate

                                                   ~t'- -

0.004%/s (> 1 ppm DO) I

                                                                   ~~          * .JKt      **                      . Ju.~"               Dissolved Oxygen
                                                                                                                                                                               ~~0     !     ~

0 >1 ppm 6 0.002%/s (> 1 ppm DO) ** 0 <0.05 ppm

                           .o      0.004%/s (0.05 ppm 00) +--~~~1<------:l 1 o2 : -

0.4%/~ (Air) I 6

• I Air 0.4! or 0. 01%~s) 0 50 100 150 200 250 300 350 0 50 100 150 200 250 300 350 Temperature ("C) Temperature ("C)
• Fatigue life in LWR environments is decreased above 150°C if the strain rate is below 1%/s and DO level is above 0.04 ppm
• Only moderate decrease in fatigue life at temperatures below 150°C or when DO levels in water is below 0.04 ppm 25 Effect of Surface Roughness Type 316NG SS Heat 0432804 Heat P91576 Type 304 55 Sawtooth Waveform 289"C ~ Air 6 Air 289"C Strain Rate
• 0.00410.4%/s 1.0 [> PWR 0 PWR 1.0 o Air

                                                    'V         BWR Strain Rate: 0.004%/s in Water 0          BWR            e:.                                                      6      Simulated PWR Water 0.4 - 0.004%/s in Air                                         .,;
                        \1    [> [>        -~                                                                  -o               * ..... /1£                  -Q                         Best-Fit Air
                      """ .. _                     .. ..                           Best- Fit Air               .a
                         *      * - ,_!>A             r>.' tt> . _                          ./                 ~                        * --._);.--{;.        *       ** **o*..        /

c: ASMECode jl ., r:,.* --- . />

                                                   * - . , . , __ t>.**                     . .......
                                                                                                               ~

c: ASMECode ' . - * -. - . ' --~* -** * * * ~~

    ~                                                                            *-- t:.                       ~                   Design Curve                                     * - *-

en 0.1 Design Curve Open Symbols: Smooth Specimens

                                                                                                *-*-           en         0 .1 Open Symbols: Smooth Specimens Closed Symbols: Rough Surface, 50 grit paper                                                                    Closed Symbols: Rough Surface, 50 grit paper Fatigue Life (Cycles)                                                                                              Fatigue Life (Cycles)

• For SSs, fatigue lives of rough specimens are lower than those of smooth specimens both in air and low-DO water
• For carbon & low-alloy steels, fatigue lives lower only in air, in high-DO water, lives of smooth & rough specimens are the same 26

Effect of Flow Rate A333-Gr 6 Carbon Steel (High-S) A333-Gr 6 Carbon Steel (High-S) _! ..- * ** - A br" .. . - *** ---: ::: : : ::: . . ~ - -- - -** ----8 DO (ppm) DO (ppm) 289°C - e - - 1.0 289°C - - & - 1.0 Strain Amplitude 0.3% -- ~-- - 0.2 Strain Amplitude 0.6% *- -- 0.2 102 Strain Rate 0.01%/s - A *** 0.05 Strain Rate 0.001 %/s - A**- 0.05 101 WL~WL~~~~~~~~~~~ 1o*s 10-4 1o*3 1o*2 1o*1 1oo 10 1 10"5 10 4 10"3 10"2 10"1 10° 10 1 Flow Rate (m/s) Flow Rate (m/s)

• In high-DO water, environmental effects decrease with increasing flow rate, lives are factor of 2 greater at -;:.::::,7 m/s than at 1o- 5 m/s
• Increasing flow rate has no effect on fatigue life of austenitic SSs 27 Fatigue Mean Curve for Ni-Cr-Fe Alloys in Air ASME Code Mean Curve Austenitic SSs 0.1 0.1 10 4 1~ 1~ 1~ 1~ 1~ 1~ 1~

Fatigue Life (Cycles) Fatigue Life (Cycles)

• Fatigue £-N data for Alloys 600 and 690 show very good agreement with the ANL model for austenitic SSs
• The data for Ni-alloy welds are also consistent with the ANL model in low-cycle regime and show the model is somewhat conservative in the high-cycle regime 28

Fatigue Life of Ni-Cr-Fe Alloys in LWR Environments ASME Code "V 0 'l*:b.* Mean Curve Austenitic SSs

                                                                            ';) ';)';) o ..  -1(

0 * * . ..._ 0.1 Fatigue L ~e (Cycles) Fatigue L~e (Cydes)

• Similar to austenitic SSs, environmental effects on fatigue life ofNi-Cr-Fe alloys are greater in low-DO than high-DO water
• Under similar loading & environmental conditions; however, effect is considerably less for Ni-Cr-Fe alloys than for SSs 29

     ..,,...to~!' RfQ(I<..,.

/ ~ .. ~ E Fatigue Strain vs Life (E-N) Curve ~

.-:,. ., ....... ,.     .0~
                             ~

• Fatigue design curve obtained from best-fit curve of fatigue £ - N data expressed in terms of modified Langer equation; ln[N] = A - B ln( Ea-C)
• Constant A varies from heat to heat.

Distribution of A assumed to represent variability in fatigue life due to material variability 30

Cumulative Distribution of Constant A 1.0 *..:.:. ~

• 1.0

                - l ow-Alloy Steel                     ~-
                                                                                           - Low-Alloy Steel Water Environment

_ Air I

                                                                                                                       ..L
                                                                                                                     ~

0.8 0.8 75th Percentile 75th PercentOO

ttr u..

g

                                   ,......,  ,_...                                 .il 0.6
                                                                                   ~         Median 5.747                       327 ~a~;~lnts _

1 Median 6.449 358 Data Point& - 19 Heats - 6

                                                                                                                ~
                                             .....         6      $eyl!(n\
                                                                                   ~                             -r            6      S.,'loml
                                   >-1
                                    ..a:                   'V     "'"'

A302-B 3 0.4 1-11"~1 "6 E "' A302-B

                                                                  -~

0 0 A533-8 !AI

                                   'i-' 1                 <>      A53J.B 1 u"                                          <>     A533-8(1)
                                 ,~*

• A533*8 5 251h Percentile A533*8 (5) 251b X A5l3-8 )

Peroon X A533-8(M)

                         'le "E                              A508-2 1i 0.2              ~
                                +--                       *"'

0

                                                           <l A5()6..3 1 A508-3 7 A508( )

0.2 I ,__ ~ 1_ 0 A508-2 (1) A508-3 (I) A508-3 (7)

                                                           !>. 17MnMoV64                                                    <l     A508 (M)

A 15MnNi63 A 15MnNI63

                         >)f(.

0.0 0.0 5 5.5 6 6.5 7 7.5 8 8.5 4 4.5 5 5.5 6 6.5 7 7.5 8 Constant A ConstantA

• The 5th percentile of these distributions give £-N curve that is expected to bound fatigue lives of 95% of heats of material

      & test conditions of interest 31 Carbon and Low-Alloy Steels Air   ln(N] = 6.583 - 1.975 ln(Ea-0.113)                                                  (CSs) ln[N] = 6.449 - L8081n(Ea-0.151)                                                    (LASs)

Env ln[N] = 5.951- 1.975 ln(Ea-0.113) + 0.101 S*T*O*R* (CSs) ln[N] = 5.747 - 1.808 ln(Ea-0.151) + 0.101 S*T*O*R* (LASs) where S* = S (S ~0.015 wt. %) S* = 0.015 (S >0.015 wt.%) T* = 0 (T < 150°C) T* = T- 150 (T = 150 to 320°C) 0 *= 0 (DO < 0.04 ppm) 0 * = ln(D0/0.04) (0.04 ppm < DO ~ 0.5 ppm) 0 * = ln(12.5) (DO > 0.5 ppm R* =O (R > 1%/s) R* = ln(R) (0.001 ~ R ~ 1%/s) R* = ln(O.OOl) (R < 0.001 %/s) 32

Wrought & Cast Austenitic SSs Air ln[N] = 6.891- 1.920 ln(Ea-0.112) Env ln[N] = 6.157-1.920 ln(Ea-0.112) + T*O*R* where T* = 0 (T < 150°C) T* = (T- 150)/175 (150:::; T < 325°C) T* = 1 (T ~ 325°C) 0* = 0.281 (all _DO levels) R* =0 (R > 0.4%/s) R* = ln(R/0.4) (0.0004:::; R:::; 0.4%/s) R* = ln(0.0004/0.4) (R < 0.0004%/s)

• A single correlation can be used for wrought & cast austenitic SSs; fatigue limit based on results by Tsutsumi et al. & Jaske & O'Donnell, slope Band constant A determined from best-fit of fatigue E-N data, and obtained from cumulative distribution of A for various data sets 33 Fatigue Life of Components
• Available information reviewed to better define adjustment factor on life that must be applied to mean-data curve to account for effects of variables that influence life but were not explicitly addressed in the data Parameter ASME Code Presented Study Material Variability & Data Scatter 2.0 2.1 - 2.8 Size 2.5 1.2 - 1.4 Surface Finish 4.0 2.0- 3.5 Loading History 1.2 - 2.0 Total Adjustment Factor 20 6-27
• Monte Carlo simulations performed to determine distribution of A for adjusted fatigue curve that represents behavior of actual component.

Use material variability & data scatter results from present analysis Assume a lognormal distribution for effects of size, surface finish, & loading history, & min and max values of adjustment factor assumed to represent 5th and 95th percentile, respectively Assume effects can be considered as independent based on engineering judgment 34

Fatigue Design Adjustment Factors 10 1.0 ,.,.,--.--r-r-r-r-.-r"T-r-r-r:>'"'..,....,.-~""T""T">l

                            . _ Low-Alloy Steel ----j----/'/ ----j---...-...jf.L-
                                                                               / -1     r- Stainless Steelf - ---/-f------1----,:----1 A

_ ir - Components -f1

                                                          '---+---+---l                    AI

_ ., - Components -f-t---+-+--1

                                  -    *** -Test                                                  -- ~ Test 0.8                Specimens c__--+---+--+               0.8                Specimens  --+---+-r---+

l 0.4  : . ____;__ ~ ; E --+--+---+-+:------+-----t

                               ------7-- H -+---+--             -+-' :. - -
                               ,....-+-o.. '*

o.z ,....-+- ~ :u

                                                                    *u--
                                                                     ~ cg __
                                     . en :                    , i :~--

f - - -hl:/ 1-----+---11-:>:_! - - 4 6 ConstantA ConstantA

• Monte Carlo analysis suggests adjustment applied to mean values of specimen fatigue life to bound component fatigue life of 95% of population is ::::::12. Thus, current Code requirements of factor of20 on life is conservative by about a factor of::::::1.7 for components 35 t.*" RE'ol.t

/....              <-.,0~    Effect of Environment 0

\~... , l on Code Fatigue Evaluations

       .......... .0

• Conservatism in current Code fatigue evaluations will tend to offset effect of environment on fatigue life
• Conservatism in Code fatigue evaluations may arise from:

               - fatigue evaluation procedures (stress analysis rules & cycle counting)
               - adjustment factors of 2 & 20

• Analysis suggests conservatism associated with factor of 20 is modest; that associated with stress analysis rules can be much greater
• Code permits improved approaches to fatigue evaluations, e.g. , finite-element analyses, fatigue monitoring, etc.,

that can significantly decrease the conservatism

               - suggests need to explicitly address environmental effects 36

Methods for Incorporating Environmental Effects

• Two approaches proposed for incorporating effects of L WR coolant environments into Code fatigue evaluations:

        - develop new fatigue design curves for LWR environments
        - use an environmental fatigue correction factor Fen

• Because fatigue life in LWR environments depends on several loading & environmental parameters, design curve approach would" require developing multiple design curves to cover range of conditions or a conservative bounding
• curve
• The Fen approach is relatively simple and flexible enough to address effects without unnecessary conservatism 37 Fen Method for Incorporating Environmental Effects
• Fen is defined as ratio of fatigue life in air at RT to that in water unoer service conditions ln[Fen] = ln(NRTair) -ln(Nwater)

Fen= exp(0.632- 0.101 S*T*O*R*) (Carbon Steels) Fen= exp(0.702- 0.101 S*T*O*R*) (Low-Alloy Steels) Fen = exp(O. 734 - T*O*R *) (Stainless Steels) Fen= 1 (Ea:S0.07% CLAS & :50.10% SS~)

• To incorporate environmental effects, fatigue usage based on air curve is multiplied by Fen Uen = U, Fen,!+ U2 Fen,2 .... Un Fen,n
• Usage in air is determined from design curve that is consistent (or conservative) with respect to existing fatigue E-N data.

Current Code curve for SSs should not be used because it will yield nonconservative estimates of CUF 38

Environmental Correction Factor for Ni-Cr-Fe Alloys Fen= exp(T*O*R*) (Ni-Cr-Fe Alloys) where T* = T/325 (T < 325°C) T* = 1 (T 2: 325°C) R* =0 (R > 5.0%/s) R* = ln(R/5 .0) (0.0004::; R::; 5.0%/s) R* = ln(0.0004/5.0) (R < 0.0004%/s) 0 * = 0.09 (NWC BWR water) 0 * = 0.16 (PWR or HWC BWR water) (Ea :S 0.10%)

• Fatigue usage in air is determined from the new fatigue design curve for austenitic SSs developed from the ANL model 39 Other Proposed Changes in Code Mean Curve for Austenitic SSs wtrJ 1.0 c

                                                  £!

en 0.1 0.1 1~ 1~ 1~ 1~ 1~ 1~ 1~ 1~ 1~ 1~ 1~ 1~ 1~ 1~ Fatigue L ~e (Cycles) Fatigue L~e (Cydes)

• Current Code mean curve is not consistent with existing fatigue data in air at strain amplitudes <0.3%, the Code mean curve predicts significantly longer fatigue lives than those observed experimentally 40

Ste~'l

                      ~\

1 A2stenitic Stainle1s

                                                                 *1           Air up to 371"C (700"F)

I I I I

                                  ~
                                                                -       * * * - ASME Code Curve
                                                                - - New Design Curve Based on the ANL Model              -
                                       "' ~
                                                ~         * ... .
                                                       ~ ~ - --

E = 195.1 GPa 1' . I I t-- au = 648 1 MPa cry= 303.4 MPa

                                ..1      .. 1 10 1      102      103    104   105      106           107         108     109     10 10  10 11 Number of Cycles N

• Fatigue design curve based on the ANL correlation for austenitic SSs in air and a factor of 12 on life and 2 on stress 41 Fatigue Design Curve for Carbon Steels in Air

                      ~

6arbon-~teels "l UTS S552 MPa (S80 ksi) Air up to 371"C (700"F) li 0.. 6., 10 3

                                ~                                                       *e =206."8 GPa 1
                                    -~                                  -      * * * - ASME Code Curve
                                         ~.'

(j) - - ANL Model & Eq . 18 Q)

          '0
                                                ~

2 Ci E

          <1:
           "'"'~ 102                                            -

Cii Carbon Steels cr0 = 551 .6 MPa 1- * ** r- .. - -...

                         <>y = 275.8 MPa J       .1 10 1      102     103     104   105     106           107         10 8     109    1010    10 11 Number of Cycles N

• Fatigue design curve based on the ANL correlation for carbon steels in air and a factor of 12 on life and 2 on stress 42

Fatigue Design Curve for Low-Alloy Steels in Air

                                                          ..,         "'I      J      "1 r\ ~                                           Low -Alloy Steels UTS :S552 MPa (s80 ksi)

Air up to 371*c (7oo*7 I E *=206.8 GPa

               .                  *"\.
                                   *,                   -     * * *

• ASME Code Curve

                                       ~.'

(/) - - ANL Model & Eq. 18

                                           ~
                                               ~. f- ...

r- -.. i- .. Low-Alloy Steels o, =689.5 MPa

                           =

C!y 482.6 MPa

                            .. .1    ..1 10 1    102      103  104  10 5 106    107         108     109    10 10 10 11 Number of Cycles N

• Fatigue design curve based on the ANL correlation for low-alloy steels in air and a factor of 12 on life and 2 on stress 43 Extension of Mean Curve from 106 to 1011 Cycles
• An extension of the Code fatigue design curve for carbon

      & low-alloy steels from 106 to 10 11 cycles has been proposed by ASME Subgroup Fatigue Strength
        - extension takes into account the effect of maximum mean stress & is based on load-control data (R = 0) that extends up to 5 x 106 cycles
        - Stress amplitude (Sa) vs. life (N) relationship is expressed as Sa = Eea = C t N-o.os
        - Extrapolation of this curve to 10 11 cycles may yield conservative estimates 44

Extension of Mean Curve from 106 to 1011 Cycles

• In the high-cycle regime, plot of elastic-strain-vs.-life for the available fatigue data (that extend up to 10 8 cycles) yields a small slope (-0.007) instead of a fatigue limit; Manjoine & Johnson obtained an exponent of -0.01
• In high-cycle regime the mean curve for carbon & low-alloy steels can be expressed as Sa = EEa = C2 N-o.oi

  * . To develop design curve, this curve is first adjusted for mean stress effects using the Goodman relationship, then adjusted curve is decreased by a factor of 12 on life and 2 on stress to obtain the design curve 45 Fen     Method (Contd.)

• For CSs & LASs, usage factors can be based on current Code design curves, or to reduce conservatism associated with the Code factor of 20 on life, usage factors could be based on design curves developed from ANL models
• For austenitic SSs & Ni-Cr-Fe alloys, usage factors determined from the new design curve developed from ANL model
• Guidance for key loading & environmental parameters

        - Using the average strain rate for a transient yields conservative estimate ofFen
        - When results of detailed transient analysis are available the average temperature may be used in calculation ofF en 46

Operating Experience & Component Tests

• Occurrences of corrosion fatigue damage and failures in nuclear power plants reviewed in EPRI TR-106696 (1997)
• Case histories & conditions that lead to SICC in LWR systems summarized in Nucl. Eng. Des. 91, 1986

               - Strain rates are IQ- 3-1 o-5%/s due to thermal stratification, under these conditions significant effect observed in lab tests

• Applicability of laboratory data to component behavior has been demonstrated by mock- up and component tests:

               -   Katzenmeier et al., Nucl. Eng. Des. 119, 1990
               -   Kussmaul, Blind, Jansky, Intl. J. Press. Yes. & Piping, 25, 1986
               -   Lenz, Liebert, Wieting, 3rd IAEA Specialists Meeting, 1990
               -   Stephan, Masson, Intl. Conf. on Fatigue, Napa, 2000
               -   Kilian, Hickling, Nickell, Third Intl. Conf. on Fatigue, 2004 47 Type 304L SS U-Bend Tests in PWR Water at 240°C Type 304L U-Bend Tests
        ' *.                         24o*c Water, <0.01 ppm DO
          ' *..                                                               104
                                                                          ~

1l

                                                                          ~

Best-Fit Air Statisti cal Model ~ 10 3

                                                                          ..J
                                                                           § g

ro Strain Amplitude(%) u. 0.1 D. 0 Inert Env. PWR Water, 0.01%/s- + - - - + - -- - 1 o' 0.38% 0.25% I 0 PWR Watef, 0.005%/s 102 <> 0.52% (U a ends ) 106 10"5 10.. 10*3 10*2 Fatigue Life (Cycles) Strain Rate (%/s)

• Measured environmental reduction factor Fen = 10,000/ 1,728 =5.8 at 0.0005%/s & = 10,000/3,624 = 2.8 at 0.01 %/s.

Predicted values are 5.5 and 3.6, respectively 48

Regulatory Positions 49 Regulatory Position 1: Carbon and Low-Alloy Steels ./ Calculate fatigue usa3e in air with ASME cart>on steelS

                                                                                                            =

Code Analysts proce ures +

          ./ ASME Code air curves, or Q.
                                                  !    103
                                                                     '\

UTS e MPa (<80 ksl) Air up ID 371"C (700"F)

                                                                                                                 =206.aGPa
                                                                                                     * * .* ASM COcle Cut\1<
          ./ New ANL model air curves             v.r                       '\                   - - ANI. MOOel & Eq. 18
                                                  -g

./ Calculate the Fen using "'

          ./ Equation A.2 (CS),                   <

j

                                                   ~

1o2 Fen= exp(0.632- 0.101 S*T*O* f; *) cr.,*56USMPa o, =:275.8 ),Fa

          ./ Equation A.3 (LAS) 10 1       1o2     10'  10'  10 5 1o'    10 7      108      10. 1010 1011 Fen = exp(0.702- 0.101 S*T*O* f; *)                                    Number of Cycles N (Appendix A ofNUREG/CR-6909)                                                               L""""'*>ySieels UTS s562 MPo (S80 ksl)

Air up to 371"C (700"F) ./ Calculate the environmental fatigue usage '\ E ., 205.8GPa CUen) .

                                                   <n
                                                   ' " 1ol B
                                                                            '\
                                                                                                -   * * *

• ASME COcle CU\o<

                                                                                                --ANLModd&Eq 18
                                                   "'~

Uen = U1 Fen,!+ U2 Fen,2 **** Un Fen,n < j 1o2 lOIW*AIOojSieels o11 '* ~-5MPa o, = 4&2.15 MPa 50 10 1 1o2 103 iO' 10 5 100 10 7 lo' 10. 1010 1011 Number of Cycles N

Regulatory Position 2: Austenitic Stainless Steels v" Calculate fatigue usage in air with ASME Code Analysis procedures+

        ./ New ANL model air SS curve v" Calculate the Fen using
        ./ Equation A. 9 Fen = exp(0.702- 0.101 S*T*O* f; *)

(Appendix A ofNUREG/CR-6909) v" Calculate the environmental fatigue usage (Uen)

                                                                                           ~~steniti:l Stainl~~s Ste~J
                                                 ~                                  l         Air up to 371 DC (700DF)

I I I I r\

                                                                                    -  * * *

• ASME Code Curve

                                                                                    - - New Design Curve Based on the ANL Model         -
                                                              ~
                                                                   ~-
                                                                        ~     * -.,

E = 195.1 GPa au=648.1 MPa

                                                                   '        ~ r--...:*

ay = 303.4 MPa

                                                       ..J      ..J 51 101   102      103    1o4  105     106     107       108     109   10 10  1011 Number of Cycles N Regulatory Position 3:

Ni-Cr-Fe Alloys (e.g., Alloy 600 and 690) v" Calculate fatigue usage in air with ASME Code Analysis procedures +

        ./ New ANL model air SS curve v" Calculate the Fen using
        ./ Equation A.14 Fen= exp( T*O* f; *)

(Appendix A ofNUREG/CR-6909) v" Calculate the environmental fatigue usage (Uen)

                                                                                           ~~steniti:l Stainl~~s Ste~J
                                                 ~\                                 "1        Air up to 371 DC (700DF)

I I I I 1\

                                                                                     - * * *

• ASME Code Curve

                                                                                    - - New Design Curve Based on the ANL Model
                                                                                                                         ~
                                                              "~ -
                                                                       ~      *- ... .

E =195.1 GPa f-- au =' 648.1 'MPa

                                                                            ~ t----.: *---

ay =303.4 MPa I .J 52 10 1 102 103 1o4 105 106 107 108 109 10 10 10 11 Number of Cycles N

Summary

• RG 1.207 endorses the use of new air curve for SSs
• RG 1.207 endorses the Fen methodology
• Guidance on incorporating environmental correction factor to fatigue design analyses

     -Appendix A ofNUREG/CR-6909 Rev. 1

• NUREG/CR-6909 Rev. 1 describes in detail the technical basis 53 Resolution to Public Comments on DG-1144 and Draft NUREG/CR-6909 Hip6lito J. Gonzalez Corrosion and Metallurgy Branch Division of Fuel, Engineering and Radiological Research Office of Nuclear Regulatory Research (301) 415-0068 hjg@nrc.gov Omesh K. Chopra Nuclear Engineering Division Argonne National Laboratory (630) 252-5117 okc@anl.gov Presented to Advisory Committee on Reactor Safeguards Subcommittee on Materials, Metallurgy, and Reactor Fuels Rockville, Maryland December 6, 2006 54

Resolution of Public Comments

• 8 correspondents submitted a total of 56 comments on DG-1144 and draft NUREG/CR-6909

                      -All comments addressed individually

• Final RG 1.207 and NUREG/CR-6909 Rev. 1 reflects the resolution of these comments
• 6 main issues identified 55 Resolution of Public Comments (cont.)

StaffResponst> to Public Comments on DG-1144 and Draft NUREG/CR-6909

1. SoUJ"tf Comment'"" ResponsE' 1-lo. Each Conm1ent appears individually in this cohmu1. NRC staff response for each conunent.

                                                                                !dl.CB20::56
                                                                                !rn.Ccs:!i'~lofl Swttt \1:  Rol:m E. Bmn. GE Fl!qyNalur Sa.lrt1VD: C.*tnyC.Sk:ls,G.C.SilifsAi~s.Co:u:llq~

56

Resolution of Public Comments (cont.)

• Six issues (comment id #' s):

1. Operating experience and applicability of specimen data (1, 7, 14, 16, 45)

2.

• Details on approach (22, 24, 27, 37)

3.

• Ni-Cr-Fe alloy fatigue curve (20, 25, 44)

4. Burden due to increase in locations required to be analyzed (2, 43)

5. Overly conservative position (4, 5, 15)

6. ASME Code case (56) 57

1. Operating experience and applicability of specimen data (1, 7, 14, 16, 45)

Issue:

• There is no operating experience that supports the need for these conservative design rules.
• Comments questioning the applicability of specimen data being representative of actual components in service.

Staff Response:

• Numerous examples of fatigue cracking of nuclear power plant components reported- EPRI TR-106696.
• Applicability of laboratory data to component behavior has been demonstrated by mock-up and component tests (references provided in previous presentation). ']n fact, is the basis for the current ASME Code fatigue curves.

58

Issues:

• References made to other guidance containing similar Fen approach (Japan) also acceptable/endorsed?

      * "Since DG-1144 utilizes a similar Fen methodology to that evaluated in MRP-47, Rev. I, the issues identified in MRP-47, Rev. I. are considered to be equally applicable to the DG-1144 methodology. Some, but not all, of the issues raised in MRP-47, Rev. I have been specifically addressed in DG-1144. Based on this, the MRP would like to see clarification on the remaining issues included in DG-1144 or the supporting document".

Staff Response:

• The papers listed in NUREG/CR-6909 are for reference only.

Section C, Regulatory Position, of the regulatory guide contains the methodology endorsed by the staff.

• The level of analytical detail discussed on additional items on MRP-47, Rev.l are beyond the scope of this regulatory guide.

59

3. Ni-Cr-Fe alloy fatigue curve (20, 25, 44)

Issue: Provide guidance for Ni-Cr-Fe alloys (e.g., Alloy 600 and 690). Staff Response: The staff incorporated Fen methodology for Ni-Cr-Fe alloy

• materials into RG 1.207 (RP 3) and NUREG/CR-6909 Rev. 1 (Section 6).

60

4. Burden due to increase in locations required to be analyzed (2, 43)

Issue: Increase in the CUFs will lead to more analyzed piping break locations, to more installed pipe whip restraints, and to designs that will be more detrimental for normal (thermal expansion) operating conditions. Staff Response: Staff will consider a justified modification with the appropriate technical basis of the fatigue criteria for postulation of pipe breaks if implementation of the current criteria results in a significant increase in the number of required pipe whip restraints. 61

5. Overly conservative position (4, 5, 15)

Issue: Commenter believes that the alternative methods for fatigue analysis provided in NUREG/CR-6909 and DG-1144 are too conservative andshould not be used for the design of new reactors. Staff Response: The staff position is based on a 95% confidence that there is less than 5% probability of fatigue crack initiation. Implementation of this criteria resulted in a carbon steel and low-ally steel air curves which are less conservative than the existing ASME Code curve 62

6. ASME Code case(56)

Issue:

   "ASME will continue to develop other Code Cases covering alternative ways of addressing [the impact of the L WR environment} ... and the Code Case will be issued early in 2007. Once these Code Cases are issued, ASME requests the NRC to endorse these Code Cases in a revision of the Regulatory Guide 1. 84 ".

Staff Response: The NRC staff'will consider endorsing available ASME Code Cases through its normal process for revising Regulatory Guide 1.84. 63 Conclusion RG 1.207 is ready for issuance

• Final RG 1.207 and NUREG/CR-6909 Rev. 1 reflects the resolution of these comments
• Final RG 1.207 and NUREG/CR-6909 Rev.1 will be published by March 2007 (High priority RG)
• Seeking ACRS concurrence to publish final effective guide 64

SETTING THE STANDARD ASME Nuclear Codes and Standards Comments on Draft Regulatory Guide DG-1144- "Guidelines for Evaluating Fatigue Analyses Incorporating the Life Reduction of Metal Components Due to the Effects of the Light- Water Reactor Environment for New Reactors" Advisory Committee on Reactor Safeguards Subcommittee on Materials, Metallurgy, and Reactor Fuels December 6, 2006 Rockville, Maryland 1

J('f!:~";.' -1\-SMt: ASME Nuclear Codes and Standards Representatives Ken Balkey, Vice President, ASME Nuclear Codes & Standards I Chair, ASME Board on Nuclear Codes and Standards (BNCS) Kevin Ennis, ASME Director, Nuclear Codes & Standards Bryan Erler, Vice Chair, BNCS Strategic Initiatives I Member, ASME Boiler & Pressure Vessel Code Subcommittee III Dr. Chris Hoffmann, Member, ASME B&PV Standards Committee I Member, ASME B&PV Code Subcommittee III

                 . Bruny, Member ASME Subgroup on J:)esign onVes*

(!A":.:,

Ml'1t: Topics

• ASME Nuclear Codes and Standards Overview
• Open Comments by ASME Subcommittee III Groups Related to Draft Regulatory Guide DG-1144
• Background on ASME Efforts to Address the Impact of Environmental Fatigue
• Technical Discussion on ASME Approaches 2

Centers Strategic Management Board on Board on Board on Standardization Safety Codes Conformity and Testing and Standards Assessment Board on Codes & Standards Operations Board on New Development Over 3,000 volunteers participate in the Codes & Standards process with -BOO

vonJmEters _in Nuclear Codes & Standards Board on Nuclear Codes & Standards Standards Committees Nuclear Subcommittees of

• Operation & Maintenance BPV Code Committee
• Qualification of Mechanical
• III- Nuclear Power Equipment
• XI- Inservice Inspection
• Nuclear Air & Gas Treatment
• Nuclear Accreditation
• Nuclear Quality Assurance
• Nuclear Risk Management
• Nuclear Cranes 3

    -~i';.'J

-MME Nuclear Codes and Standards Consensus Process Participation and Achieving Consensus

• Committees made up of world experts
• Voluntary international participation
• ASME Codes and Standards relies on industry supporting participation
• Identify technical basis to respond to identified needs
• Resulting consensus must be technically accurate, assure adequate safety, and be practical and workable
• ASME provides the structure and admi.nistrative Open Comments by ASME Subcommittee III Groups Related to Draft Regulatory Guide DG-1144
• Successful experience from today's operating reactors related to environmental fatigue raises a question as to if there is a need to change ASME B&PV Code Design Rules?
• Environmental fatigue effects only the inside surface of a component that is notconsistent with test conditions of Fen approach and current design practices
• The test data cited were obtained using methodology that is inconsistent with the basis of the cuJTent ASME fatigue curves The failure definition, specimen size, surface finish, loading application and temperatures were different; The original tests are based on through-wall cracking whereas the new tests are based on 25% load drop urate comparisons cannot be made; Fen

                   . ted are not representative of,nuc1~~,, '"'*~*-- A'"'"""h
                               ~..,..._," ., -~- *- ~~::_~..:.:~L '=** !~ ;: '* :* : ,':.:-:.~; :.;;_; " *.. ~ '

4

Open Comments by ASME Subcommittee III Groups Related to Draft Regulatory Guide DG-1144

• Design margin ofDG-1144 is too conservative
• Increased conservatism in ASME B&PV Code Design Fatigue Rules could result in undesirable impacts

     - Conservative design will result in higher fatigue usage factors
     - Increase in postulated pipe break locations and restraints
     - Impacts plant operations and inservice inspection

• Does implementation of the proposed approach result in unnecessary Code and regulatory burden on users without a commensurate safety benefit?
• Implementation of proposed approach to piping Code design

*. rules has a number of unresolved issues and questions
       .        MRP-47)                                                                                       -'* ..

• Background on ASME Efforts to Address the Impact of Environmental Fatigue PVRC Steering Committee formed by ASME BNCS in response to NRC 1991 Branch Draft Technical Position on Environmental Effect on Fatigue ASME members participate with NRC on fatigue issues I 99311994 (GSI-166 and SECY-94-191)

WRC Bulletin 404 Environmentally Assisted Cracking Fatigue Crack Growth 1995 Curves; Bettis Studies 1996 ASM E Section X I Appendix L added to address operating plant fatigue issues 1999 ASME Section XI Code Case N-643 FCG Rate Curves issued 2000 Section XI Task Group Appendix L formed to adopt PVRC r~commendations Section Ill Task Group on Environmental Effects on Fatigue formed ASME Section Ill Task Group closed with recommendations for Subgroup Design to evaluate if design rules should b.().£jianged

                  -                                                                ..... --~.:~o.,'-:'~~i- ..;;*~*' ,.
                            '*- -*...._~.~~::-:'..~:.G:£:..~'~sil';6-S~.:::.t.it*1.:-...;..- ,.

5

Technical Discussion on Approaches that ASME has recently Explored

1. Make no changes to ASME Boiler & Pressure Vessel (B&PV) Code design rules; Treat impact of environmental fatigue as an operating plant life issue

2. Adopt fatigue curves that envelope test results in today's database; ASME Code Case under review

3. Utilize an environmental conection factor (Fen) similar to NRC proposal in Draft Regulatory Guide DG-1144 (without the extra conservatism in the

1. Make No Changes to ASME B&PV Code Design Rules

• Many members of Subcommittee lii and the Subgroup on Design believe the cun*ent rules are acceptable to address environmental fatigue impact on cutTent LWR nuclear plants
• The French have concluded that the RCC-M Code, which is based on ASME Section III, adequately covers environmental fatigue
• Japanese representatives on ASME Subcommittee III groups believe that their design rules, similar to ASME Section III, are adequate by treating environmental fatigue as an operating inservice item

      * -.Monitor operating conditions-load
        * * . * :and...........

numbers of events . ,.,,'i'""" *

                               ;.. ~.. ..._~.::::::;;._~~Cff...~;<;!J.::.f::F:'f,;:c*.M~** .. .

6

2. Adopt Fatigue Curves that Envelope Test Results in Today's Database

• ASME Subcommittee lU has put significant effort into developing a Code Case with new fatigue curves that envelope all data as best as possible
• This approach is the most conservative, but it does not reflect actual nuclear plant conditions
• Concern that added pipe supports and whip restraints resulting from this approach will make the plants less safe

3. Utilize an Environmental Correction Factor (Fen)

• ASME is attempting to develop a Code Case implementing a similar Fen approach as DG-1144 con*ecting the concems outlined in our comments above
• This effort has resulted in two concerns that continue to hold up a consensus agreement

  - Ability to develop implementation rules for piping that would not be excessively complicated
  - Lack of agreement on the need Concern that added pipe supports and whip restraints resulting
   .     *s aRproach will make the plants J~.~s*. §~f~ *.
           .    " "'~. *~-----*- ....--~.-::..::..:-.:;.Zi-;;;."-2...:.:.*:-'!"*~.:;;:~~*:~~~<>;*f;;."': **' . . * .. .'

7

Sununary and Future Actions by ASME

• The impact of environment is one of the factors that is considered in ASME B&PV Code design criteria; ASME is wrestling with the need to change current design requirements and if there is a need, how the change would be implemented based on operating experience and considering safety and economic impacts
• ASME will consider adopting the proposed Regulatory Guide DG-1144 approach in the format of a Code Case to enable thorough review by ASME constituents
• ASME will continue to develop other Code Cases covering altemative ways of addressing the impact of environmental fatigue ME plans will continue to foster cooperative efforts for better understand the impact ?f~n
• _,

                        ~--**- ... *--*-**.o::.:..... ~~*~-** . .-;* ,.

8

AREVA September 22, 2006 NRC:06:039 Rules and Directives Branch Office of Administration ATTN: Mr. Hipolito J. Gonzalez U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Comments on Draft Regulatory Guide DG-1144 and NUREG/CR-6909 Ref.: 1. Federal Register Notice (71 FR47584), Draft Regulatory Guide: Issuance, Availability

Dear Mr. Gonzalez:

The NRC solicited comments on both Draft Regulatory Guide DG-1144, "Guidelines for Evaluating Fatigue Analyses Incorporating the Life Reduction of Metal Components Due to the Effects of the Light-Water Reactor Environment for New Reactors," and NUREG/CR-6909, "Effect of LWR Coolant Environments on the Fatigue Life of Reactor Materials," in the referenced Federal Register notice. The NRC requested comments by September 25, 2006. AREVA NP appreciates the opportunity to provide comments on draft Regulatory Guide DG-1144 and NUREG/CR-6909. In general, AREVA has significant comments regarding the need for the proposed conservative methods as well as acceptability of some of the technical methods. These comments are outlined below.

1. General Comments from AREVA NP

a. Regulatory Analysis for DG -1144 notes that:

After about 20 years of research effort addressing the environmental degradation of fatigue crack nucleation, it has become apparent that exposure to light-water reactor environments has a detrimental effect on the fatigue life of metal components, which affects the major categories of structural materials (i.e., carbon steel, low -alloy steel, and austenitic stainless steel). AREVA agrees with laboratories fatigue tests results concerning demonstration of the role of pressurized water reactor (PWR) environment on the low cycle fatigue (LCF) behavior of reactor materials. However, AREVA is not aware of any operating experience that supports the need for these conservative design rules. The NRC should cite specific examples where operating events associated with a significant environmental effect have been at the root cause of fatigue failure. The NRC should also cite where in the fatigue analyses AREVA NP INC. An AREVA and Siemens company 331 5 Olcl Forest Roed. P 0. Box 1 0935 Lynchburg. VA 24506*0935 T~:-)1.: 434 832 30!)0- Fax* 434 83:2 3840- www.arevacorn

Mr. Hipolito J. Gonzalez NRC:06:039 September 22, 2006 Page 2 supporting the original design, it was necessary to accountfor environmental effect to demonstrate the need for this regulatory guidance.

b. The Regulatory Analysis states that the "costs associated with implementing this guidance are expected to be minimal." AREVA believes that an increase in the Cumulative Fatigue Usage Factors (as suggested in DG-1144) will lead to more analyzed piping break locations, to more installed pipe whip restraints, and to designs that will be more detrimental for normal (thermal expansion) operating conditions.

• In addition, there will be more restrictions on the Design Transients (in the Functional Specifications) and the analyses will have to be performed with added accuracy, such as performing elasto-plastic finite element analyses, to be able to reduce the conservatisms inherent to the current design and analysis methods.

However, it is not usual to perform elasto-plastic finite element analyses at a design stage and this added complexity to new plant designs is unwarranted. Analysis costs will increase significantly owing to the involved nature of the F(en) calculation, particularly related to the determination of strain rate. This method will also require more detailed analyses of piping and components due to the severe nature of the F(en) penalty. For example, it can be anticipated that more locations in stainless steel piping will have to be evaluated using finite element approaches (NB-3200) instead of the traditional simplified rules in NB-3600.

c. The Regulatory Analysis has the following statements:

This guidance will complement and be consistent with current established practices applied throughout the commercial nuclear power industry for license renewal evaluations. The practice reported in NUREG/CR-6260 applied to several plants and identified

• locations of interest for consideration of environmental effects using the fatigue design curves that incorporated environmental effects. Section 5.4 of NUREG/CR-6260 identified the following component locations to be most sensitive to environmental effects for PWRs.

1. Reactor vessel shell and lower head

2. Reactor vessel inlet and outlet nozzles

3. Surge line

4. Charging nozzle

5. Safety injection nozzle

6. Residual Heat Removal system Class 1 piping It is not understandable why the guidance for new plants, in spite of better materials, more modern nondestructive testing technologies, and improved manufacturing process, is 11ot restricted to a limited number of locations. In lieu of evaluating the entire Class 1 systems for the environmental effects on fatigue, AREVA believes an approach that parallels the license renewal approach would provide more reasonable assurance that the environmental effects are bounded sufficiently.

Mr. Hipolito J. Gonzalez NRC:06:039 September 22, 2006 Page 3

d. The Regulatory Analysis for DG -1144 notes that:

The ASME Board of Nuclear Codes and Standards, Subcommittee on Environmental Fatigue, is still developing a Code Case and non-mandatory procedure to provide guidance regarding the application of an environmental correction factor for fatigue analyses. This task was assigned to the PVRC Steering Committee on Cyclic Life and Environmental Effects, which recommended revising the Code fatigue design curves (Welding Research Council Bulletin 487, "PVRC Position on Environment a/ Effects on Fatigue Life in LWR Applications"); however, despite years of deliberation, the ASME Subcommittee on Environmental Fatigue has not yet approved this proposal and has not reached a consensus regarding the approach or methodology that will be used for guidance. AREVA does not believe the NRC should establish very conservative design rules without peer consensus. The fact that consensus has not been reached in the industry highlights both that the research is not sufficiently finalized to be conclusive and that the correct method of treatment of environmental effects is not clearly established. For example, there is not enough evidence to support the combination of all detrimental effects. It is not appropriate to treat simultaneously all the detrimental effects of size, surface finish, loading history, data scatter, material variability, dissolved oxygen in the water, strain rate, and temperature to calculate the environmental fatigue penalty. AREVA believes that there are cases where, when one effect is taken at its worst (at saturation), the other effects do not further negatively affect the fatigue resistance of the component. Therefore, AREVA believes that for fatigue the "Cumulative Penalties" methodology is overly conservative.

e. The current ASME Code fatigue methodology is overly conservative. Examples of the conservatisms that are inherent to methodology include:

o use of conservative values for fatigue strength reduction factors, o the piping stress indices, o the piping stress methodology, o use of Tresca criterion for the calculation of the stress intensity, o use, in the design methodology, of minimum specified mechanical properties in place of representative materials properties,

• the fatigue plasticity penalty factor (f<e),
• design transients are more severe than the actual transients, o grouping various transients into analysis sets in which each set is bounded by the most severe transient in the set, and o there are fewer transients during the plant lifetime than specified in the Functional Specs.

It would be preferable to review the whole methodology rather than limiting efforts to the materials aspects.

f. There is no guidance in DG-1144 or CR-6909 regarding how to treat carbon steel and low alloy steel, which are "protected" from the primary coolant environment by stainless steel (or Alloy 690) cladding. AREVA believes it is reasonable to assume that there will

Mr. Hipolito J. Gonzalez NRC:06:039 September 22, 2006 Page4 not be any environmental effects on clad carbon steel and low alloy steel. For completeness, the guidance should address this subject.

2. Technical Comments from AREVA NP

a. The majority of the LCF tests were performed at high temperature on polished specimens in the NUREG/CR-6909. About ninety percent of the tests were done at high temperature (between 260°C and 325°C) in isothermal conditions with triangular strain signals leading to constant strain rates. These test conditions are not representative of realistic thermo-mechanical loadings applied on components during operation. Indeed, the triangular form of cycles with two slopes and a constant temperature chosen for the laboratory fatigue tests is very different from the actual cycles applied during operating transients, which contain successions of high strain rates and low strain rates with a variable temperature. Because the tests performed in the laboratory specimens are not representative of in-service reactor components, it is not clear that the F(en) factors derived from those tests apply to the components and operating conditions in a nuclear plant. *

b. After a micro-structural crack has formed, the crack depth is approximately 0.3 mm and a surface finish effect is no longer required, since the fatigue process occurs at the crack tip. Surface finish effect were only established in air. It is supposed to affect the fatigue life by a factor of three. NUREG/CR-6909 recommends treating the environmental effect on a rough surface by multiplying F(en) factor by approximately 3 but this accumulation is not proven by sufficient data obtained on representative surface at various strain amplitudes in PWR environment.

c. Loading sequence effects should not be considered as an additional penalty for the factor of 12.0, as suggested in NUREG/CR-6909. During normal operation of the nuclear power plant, the cycles are reasonably well distributed for the entire life of the plant. Therefore, the Loading Sequence effect is not required. Furthermore, such a loading sequence is not supported by reviewed and accepted experimental results.

d. There should be a real threshold for both temperature and strain rate. In other words, below a certain temperature (150°C or 180°C), or above a certain strain rate (0.4 percent or 1 percent per second) penalty F(en) value should be 1.0. That has been shown clearly in the Figure 12 of the 2005 PVP Paper No. 71409 and in the Figure 10 of the 2005 PVP Paper No. 71410. These two technical papers are from William J. O'Donnell, William John O'Donnell, and Thomas P. O'Donnell.

e. The proposition of a new fatigue curve in air is based on insufficiently supported test results and some of which were obtained on unrepresentative materials. For instance, a paper cited in the NUREG/CR-6909 [reference 105] is used as data for this fatigue curve to analyze mean stress effect. Nevertheless, the material used in this reference has an inordinate high reduction of fatigue strength due to mean stress.

In section 5.1.1 of NUREG/CR-6909, for example, it can be possible to obtain three different best-fit mean S - N curves for austenitic stainless steels types 304, 316 or 316 NG.

Mr. Hipolito J. Gonzalez NRC:06:039 September 22, 2006 Page 5 Other authors like Jaske and O'Donnell in 1977 or Tsutsumi in 2000 (see PVP 2000-Vol. 41 0-2) have also proposed best fit mean S- N curve expressions for similar austenitic stainless steels (304, 316, 310, and 347), which are different from those proposed in NUREG/CR-6909. Significant differences of about +/- 20 percent are noticed on the fatigue life according to the best-fit S - N curve selected which shows that the S - N curve determination is a function of the chosen materials and associated fatigue test database. NUREG/CR-6909 does not sufficiently demonstrate that the tested materials and fatigue test data used for the definition of a reference best-fit mean S - N curve are representative* of modern materials. The fatigue E- N data are typically expressed by using one equation to cover the two domains (i.e., LCF and high cycle fatigue (HCF)). The proposed modification of the reference mean S - N curve comes from the consideration of recent fatigue test results corresponding to the HCF domain, whereas, for reactor components, design studies are mainly concerned with the LCF domain.

f. The conclusions in NUREG/CR-6909 regarding evaluations of the mean stress effect seem to be solely based on the paper published by Bettis Bechtel Inc. (see PVP 1999 -Vol. 386). This paper suggests -for an austenitic stainless steel type 304 -

that the mean stress effect can reach 26 percent of the strain amplitude in the LCF domain and in the intermediate domain of fatigue life (N < 106 cycles). This evaluation of the mean stress effect seems too conservative and is probably mainly due to the selection of the tested materials by the Bettis Bechtel Inc. laboratory, which are not representative of modern materials. In fact, this result is essentially based on a fatigue test program performed on two stainless steel type 304 materials with very different tensile and fatigue properties. The new reference design fatigue curve in air is established in section 5. 1.1 of NUREG/CR-6909 by using insufficiently supported data, since portions of the data were obtained on unrepresentative material. The hot yield strength of the tested materials can for example vary as much as 100 percent ( 152 to 338 MPa at 288°C). This strong scatter of mechanical properties is attributed to variations in cold working from the surface to the center of the forgings supplied for the study. In these conditions, depending on the cold working level, it is well known that the material can present significant variations of its fatigue life in the LCF domain and in the intermediate domain. Fatigue strength results were obtained by AREVA for N = 107 cycles on standard polished specimens in air at room temperature on a 304L austenitic stainless steel. These results (JIP 2006- Paris, May 30-31, June 1, 2006) have shown that, in the case where progressive deformation and cold work associated to loading conditions are very limited, the maximum reduction of endurance limit is of about 10 percent, compared to 26 percent found in reference [1 05] cited in NUREG/CR-6909.

g. In NUREG/CR-6909 section 5.1.5, the surface finish conditions reproduced on LCF test specimens by using a 50-grit sandpaper to obtain circumferential striations -with an average surface roughness of 1.2 J..lm - is not sufficiently representative of those obtained on reactor components. In fact, the roughness parameter alone is not sufficient to ensure that surface finish is representative of those obtained during manufacturing of

Mr. Hipolito J. Gonzalez NRC:06:039 September 22, 2006 Page6 components. In addition, only two tests that were performed on rough specimens were reported in NUREG/CR-6909. This is not sufficient to determine a roughness surface effect. Fatigue tests performed on turned and ground specimens by AREVA (S. Petitjean - Fatigue 2002) have shown that the radius at the bottom of machining striations is a second critical parameter to characterize the surface roughness, in addition to average value of roughness amplitude. In conclusion, the reduction factor attributed to surface finish that comes from only one surface condition and a limited number of tests cannot be used for real components.

h. The majority of the LCF tests on polished specimens in NUREG/CR-6909 were performed at high temperature. Ninety percent of the tests were performed at high temperature (between 260°C and 325°C) and in isothermal conditions with triangular strain variations leading to constant strain rates.

These test conditions are not fully representative of realistic thermo-mechanical loadings applied on components during operation. Indeed, the triangular form of cycles with two slopes and a constant temperature chosen for the laboratory fatigue tests is very different from the actual cycles applied during operating transients, which contain successions of high strain rates and low strain rates with a variable temperature. Because the tests performed in the laboratory specimens are not representative of in-service reactor components, it is not clear that the Fen factors derived from those tests apply to the components and operating conditions in a nuclear plant.

3. Conclusions and Recommendation from AREVA NP AREVA recognizes the environmental effects demonstrated by laboratory fatigue tests on reactor materials. Nevertheless, AREVA believes that alternative methods for fatigue analysis provided in NUREG/CR-6909 and DG 1144 are too conservative and should not be used for the design of new reactors. The four main reasons for this recommendation are:

a. NUREG/CR-6909 only deals with materials aspects of environmental fatigue, and addresses it with a very conservative approach, while the whole methodology of fatigue is already treated at design stage with a conservatism that cannot be removed.

b. The concept of cumulative penalties, which leads to multiply by the environmental factor F(en), the reduction factor of 12, which already integrates surface finish, size effect, material variability, and loading sequence effect is too severe. In addition, AREVA believes that combining some of these effects is not justified.

c. There are too many uncertainties in the transposition of the specimen fatigue test results obtained in a PWR environment to component fatigue. For example, the results gathered in NUREG/CR-6909 are linked to laboratory tests for which the loading conditions are simple but not representative of the field operating conditions, where the loading parameters history (e.g., temperature gradient, pressure, strain rate, and dissolved oxygen) is much complex.

d. Past fatigue failures observed in nuclear power plants were due to failure of the designer/analyst to consider the actual loading conditions, such as thermal stratification,

Mr. Hipolito J. Gonzalez NRC:06:039 September 22, 2006 Page 7 turbulent penetration, and thermal mixing. These past fatigue failures were not attributed to the fact that the designer/analyst used either a non-conservative methodology or non-conservative Design Fatigue Curves. In other words, there is no field experience on steel components, either in-air or in LWR environment, that points to the necessity to modify the current Design Fatigue Curves. AREVA agrees that if, in the future, it becomes apparent that the environmental effects have an impact on component fatigue for the current fleet of nuclear power plants or for the new nuclear power plants, additional methods may need to be applied to the fatigue analyses. In summary, AREVA NP is not aware of any operating experience that supports the need for these conservative design rules. Nor does AREVA believe that the NRC should establish very conservative design rules without industry peer consensus. The guidance for new plants should be restricted to a limited number of locations consistent with the approach taken for license renewal reviews. It would be preferable to review the whole methodology, including a new methodology for selecting the list of design transients relevant for environmental analysis, rather than limiting efforts to the materials aspects. Finally, if the NRC continues with the guidance in DG-1144 and NUREG/CR-6909 as written, considerable flexibility should be provided for the use of alternative methods to those provided. AREVA NP looks forward to continued interactions with the NRC on this subject to ensure appropriate regulatory guidance is provided for new plant applications. Mr. Mark J. Burzynski is the point of contact for AREVA NP on this matter. He may be reached by telephone at 434.832.4695 or by e-mail at Mark.Burzynski@areva.com. Sincerely, Ronnie L. Gardner, Manager Site Operations and Regulatory Affairs AREVA NP Inc. cc: J. F. Williams Project 733

bee: NRC:06:Q39 R. D. Affolter F. N. Bouteille **"- . M. J. Burzynski ..-yt;i""" M. S. Carpenter~ fJr MS Co..rfe.~er D. R. Cofflin ~ T. D. Cram . R. M. Daflueas R. L. Gardner R. W. Ganthner A. Gautier ~ B. Grambau A

• R. J. Gurdal ~tv:rG J. A. Kay T. A. Mathews B. A. Mcintyre P. Myers M. V. Parece 'JJ?V/

B. Riou ~(7_ S. M. Sloan .>tvn>4.- R. Krich, Unistar}}