ML20086M871

Rebuttal Testimony of WE Baker,Md Muscente,Jd Stevenson & Re Lorentz Re Allegations Involving Aws & ASME Code Provisions

ML20086M871
Person / Time
Site:	Comanche Peak
Issue date:	02/15/1984
From:	Baker W, Lorentz R, Muscente M, Stevenson J, Stevenson J BROWN & ROOT, INC. (SUBS. OF HALLIBURTON CO.)
To:
Shared Package
ML20086M853	List: ML20086M851 ML20086M871
References
NUDOCS 8402170126
Download: ML20086M871 (37)

Text

__ _ __ _ _ _ _ . . _

e i d

I UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of )

)

I TEXAS UTILITIES GENERATING ) Docket Nos. 50-445 and

. COMPANY, et al. ) 50-446

)

(Comanche Peak Steam Electric ) (Application for Station, Units 1 and 2) ) Operating Licenses) ,

REBUTTAL TESTIMONY.0F W. E. BAKER, M.D. MUSCENTE, J.D. STEVENSON, AND R.E. LORENTZ, JR. REGARDING ALLEGATIONS INVOLVING AWS AND ASME CODE PROVISIONS Ol. Panel, please state your full names, residences, job titles, and educational and professional qualifications.

., A1. (Baker) My name is William E. Baker. I reside in Granbury, Texas. I am the Senior Project Welding Engineer employed by Brown & Root, Inc. at Comanche Peak. My educational and professional qualifications are attached to Applicants' Rebuttal Tostimony Regarding Allegations of D. Sciner and H. Stiner Concerning Weave Welding,- Welding of 'Misdrilled Holes, Downhill Welding, and Weld Rod Control, previously filed in this proceeding.

(Muscente) My name is Matthew D. Muscente. I reside in l

Houston, Texas. I am the manager of Materials Engineering )

for Brown & Root, Inc. My. educational'and professional qualifications are attached to Applicant's Rebuttal 0 y {

- +p , .r., y e. , y - e

Testimony Regarding Allegations of D. Stiner and H. Stiner Concerning Weave Welding, Welding of Misdrilled Holes, Downhill Welding, and Weld Rod Control, previously filed in this proceeding.

(Stevenson) My name is John D. Stevenson. I reside in Cleve.1snd, Ohio. I am the President and Managing Partner of Stevenson and Associates. My educational and professional qualifications are attached (Attachment A).

(Lorentz) My name is Roy E. Lorentz, Jr. I reside in Chattanooga, Tennessee. I am a metallurgical engineer specializing in welding. My educational and professional qualifications are attached (Attachment B).

02. Panel, in overview fashion please describe the major steps in making acceptable welds.

A2. (Panel) The process of making acceptable welds entails at least three distinct but interrelated activities, viz.,

(1) design of the weld joint, (2) development and qualification (testing) of a welding procedure to assure that the weld joint (and others with similar bmportant parameters) can be welded so as to meet the design strength requirements, and (3) training and qualification of welders to assure that they are capable of welding with the procedure developed, l

l 1

1 1

4 With regard to design of the weld, both the AWS and ASME Codes contain some requirements-in this area (e.g., AWS Dl.1 Code Section 2, Lecign of Welded connections, and ASME

! Code, Appendix XVII). However, neither code provides all 2

.the details necessary to design a weld joint, and both codes rely heavily on the designer to assure that the weld joint is designed to meet the design and operating loads. To do j this, the designer uses numerous reference sources and his skill as an engineer to provide a proper design which, i

pursuant to Appendix B to 10 CFR Part 50 and other 4

regulatory requirements, goea through several review and approval stages before acceptance. It must be understood i

that the ASME and AWS Codes are primarily fabrication codes and not design codes. Thus,- specific and complete design details are not included in either code.

After the weld joint is designed, a procedure to perform the weld must be' developed or obtained. This i

a process is discussed in detail-later in this testimony.

Finally, the welder must.be capable.of welding the

joint using the procedure. This entails a training and qualification-process in conformance with applicable Code

requirements to assure that the welderris qualified.

1 Q3. Panel, what 10 the purpose of this testimony? ]'

4 6

_ . . , . , , - . . , , . . .. ---m, . .

- . - . . _ . _ . . . . _ . , _ . _...._ _ - _ . . . . ~ .-

~. . . ~ . _ . . . . . . . . . - _ -. . .. - -. -

l l

1 4

A3. (Panel) This testimony will respond, in part, to CASE's i

allegations that the AWS Code contains ten specific provisions regarding welding design or welding procedures not addressed in the ASME Code, and accordingly, that welding at CPSES in accordance with the ASME Code is unacceptable. Specifically, this testimony will address

, those provisions which relate primarily to weld procedure application, as opposed to weld joint design. Those

! provisions which specifically relate to weld joint design will be addressed in later testimony regarding design. In j addition, this testimony addresses a related concern raised by the Board regarding downhill welding, weave welding, preheat requirements and cap welding.

Q4. Panel, please explain the basic philosophies of the ASME and AWS Codes as they apply to developing velding. procedures?

A4. (Panel) Both the AWS and ASME Codes include requirements for welding procedures that will result in welds that are 1

adequate for their intended uses.

The ASME Code requires that 'all welding procedures used for the fabrication and installation 1of components and their supports be qualified by test pursuant to the requirements

, of Section IX of the ASME Code. In order ~to satisfy.~these ASME requirements, each manufacturer or installer performing Code welding must conduct tests necessary to qualify each welding procedure.

l l

I

On the other hand, the AWS Code provides for the use of '

either prequalified welding procedures (i.e., not requiring qualification testing prior to their-use) or welding i procedures which are qualified by test. In short, the ASME Code allows weldi..; only with procedures based on qualification testing, while the AWS Code allows welding with welding procedures qualified by testing or with prequalified procedures.

The difference in philosophy between the AWS Code and ASME Code stems from the fact that the AWS Code covers structural welding in general along with specific requirements for use in the construction of buildings, bridges and architectural tubular structures. Thus, although its provisions for prequalification are generally applicable to any steel structure, the drafters of the AWS Code have acknowledged the limitations of that Code in stating that "when using the Code for other structures, ownces, architects and engineers should recognize that not all of its provisions may be applicable or suitable to their particular structure." (AWS Dl.2, Commentary on Structural Welding Code, Section 1.1.)- (It should be noted that in any event, the AWS Code is not applicable to pressure retaining

boundaries such as pressure vessels or. piping systems (AWS Dl.1, Section 1.1.1).)

W g ry 9 r an --

g - -

Thus, with the prequalified procedures in the AWS Code, welding may be performed without qualification testing.

However, the AWS Code recognizes that if prequalified procedures are not applicable, or if the user prefers not to S

use prequalified procedures, then the user must qualify procedures by test.

Q5. Panel, please describe the process of weld procedure qualification as allowed by both the ASME and AWS Code and used at CPSES.

A5. (Panel) In qualifying welding procedures in accordance with the requirements of Section IX of the ASME Code (as well as

• Section 5 of the AWS Dl.1 Code), a draft welding procedure is first written describing the precise status of certain variables specified in Section IX of the ASME Code ,

(essentially the same specified in the procedure qualification section of the AWS Code). A test plate or pipe is prepared and welded in strict accordance with the draft welding procedures. Mechanical tests are then performed in accordance with the requirements of QW-140,Section IX of the ASME Code to determine 'if the weldment process and parameters are acceptable and-adequate to-produce welds that will withstand design and operating loads.

I i

L I

l l

~, . , . . . _ _ _ _ _ - - -

The tests are performed using specimens removed from the test plate or pipe. Each test has a separate purpose in determining whether the weld produced using the welding procedure is structurally sound and capable of withstanding design and operating loads. The tests required by the ASME Code,Section IX (Which are essentially the same as endorsed by AWS) are as follows:

1. Tension tests, used to determine ultimate tensile strength, yield strength and ductility (reported as % elongation and/or % reduction l of area);

2. Guided bend tests, used to determine the degree of soundness and ductility of groove {

weld joints; I l 3. Charpy V-Notch Impact or Drop Weight tests, l used to determine the notch-toughness of the weldment (these tests are only performed when fracture toughness is specified in NF-2311, or for integral attachments, When required by other sections of the ASME Code); and

4. Fillet-wald tests, used to determine the size, contour, and degree of soundness of fillet welds (This test is used to qualify welding procedures When oniv fillet welds are to be I produced using that procedure) .

I If acceptable results are obtained from the testing,-

the procedure has been qualified and a Procedure Qualification Record (PQR) .is prepared listing the specified parameters used for the welding in the fona of essential and non-essential variables. ASME Section IX specifies essential and non-essential variables for each welding process. An essential variable is a change in a welding

l0 e *

) J 4

condition which will affect the mechanical properties of the

{ weldment (for example, a change in base metals, welding process, filler material or weld rod, and preheat requirements). ~ If an essential variable is changed, then i-

^

new welding procedure que';ification tests must be performed.

A non-essential variable is a change in a welding condition which will not affect the mechanical properties of a

! weldment (such as joint design, and cleaning). A change in s non-essential variable would not require requalification of the procodure, but the procedure would have to be i

evaluated, and, if appropriate, amended to include this 3 change.

06. Mr. Baker, do - all welding procedures qualified by test pursuant to the ASME Code for use at CPSES follow the

! requirements of Section IX of the ASME Code?

A6. (Baker) Yea.Section IX of the ASME Code is employed to assure that all procedures used have been properly qualified. This includes following. requirements regarding r

4 tast procedures, essential and non-ensential variables, testing of spacimens, and all other aspects which could affect the procedure qualification process.

Q7. Panel,-if a welding procedure is qualified by test in accordance with each provision of Section IX of the ASME Code, wili use of that procedure produce welds that are structurally sound and as adequate for their intended use as i .

e q , e- --+ :r -- -- w-- g-y av 8-' - ha

_9_

4 welds produced using either prequalified procedures of the AWS Code or procedures qualified by test in accordance with the AWS Code?

A7. (Panel) Yes. The ASME Code and its qualification test procedures were developed only after thorough, rigorous and complete review, testing analyses and study by literally thousands of engineers, scientists and other highly skilled and qualified professionals. Further, prior to its adoption this qualification test process set.forth in Section IX of the ASME Code received significant and extensive peer review and critique. Finally, the qualification test procedure has withstood the test of time and has proven time and time again that using it will produce welds which are adequate for their intended purpose and every bit as sound as welds produced pursuant to prequalified AWS procedures or 1 procedures qualified by test pursuant to the AWS Code.

08. Panel, in CASE's Proposed Findings at p. V-1, CASE states that " Applicants on several occasions state categorictlly that the provisions of the welding Code AWS Dl.1 do not apply at CPSES, since they ate covered by Section IX of ASME. (See Applicant's Exhibit 142F, p. 3, Mr. Finneran's >

Answer No. 8'to. Question in reference to Mr. Doyle's suggestion that AWS Dl.1 is required for weld analysis. )"

1

)

Is the- Dl.1 AWS Code applicable to welding at CPSES? 1

~

e A8. (Panel) At the outset, it should be noted that contrary to CASE's statement, Mr. Finneran did not "chtegorically" state that the Structural Welding Code, AWS Dl.1, does not apply at CPSES. Rather, in response to the question of whether the AWS Code is applicable to " safety-related pipe supports at Comanche Peak," Mr. Finneran answered "No." This was in no way meant to imply that the AWS Code is not used for any welding at CPSES. The AWS Code is. used for some welding of non-ASME components (such as some cable-tray supports and I some building structures) at CPSES. In addition, the AWS Code is frequently used by designers and engineers at CPSES as a reference (along with numerous other industry documents) in performing tasks such as design, design review or verification of weld parameters.

09. Panel, are you familiar with CASE's allegations that ten AWS Code provisions were not considered by the ASME Code and applicable CPSES welding procedures?

A9. Yes, these allegations are that the AWS Code includes certain provisions not considered.by the ASME Code or used at CPSES; i.e., (1) " Preheat requirements for welds on plates over 3/4-inch thick," (2) " Drag angle and work angles (which limit the space allowed for the welder to function,"

(3) " Beta factor for tube-to-tube welds," (4) " Multi-plication factor and reduction factors for skewed '"T" weld joints," (5) " Limitations on angularity for skewed "T"

< w 11 -

1 joi nts , " (6) " Calculations for punching (actually a j - reduction factor for the weld) shear on step tube joints,"

(7) " Lap joint requirements," (8) " Design procedure for joint of tube to tube with Beta equal to 1.0,"

(9) " Limitation on weld sizes. relative to plate thickness,"

and (10) " Calculation for effective throat of flare bevel welds." (This last item was closed out by the Board's Memorandum and Order of December 28, 1983 at p. 41).

OlO. Panel, of the nine items noted above Vhich are still open, four items (4, 5, 6 and 8, above) deal primarily with weld joint design and will be discussed in testimony.regarding l design Which will be filed at a later date. Have you conducted any research with regard to the remaining five open items (1, 2, 3, 7 and 9, above) ?

A10. (Panel) Yes, we have researched these five items Which CASE has characterized as AWS Code provisions and found that not

~

all five are AWS Code provisions.

Oll. Panel, could you please tell:us What your research entailed?

All. (Panel) We first examined the applicable AWS Code to find j out if there were any AWS Code provis.lons related to the item. Next we examined the applicable ASME Code provisions to determine if and~how the corresponding AWS Code-provis' ion

-(if any) had been taken into consideration. Finally, we

-checked to assure that the applicable procedures at CPSES took into consideration the relevant provisions.

I

. .. o-

012. Panel, wLuld you please describe the results of your evaluation for " preheat requiraments for welds over 3/4-inch thick."'

A12. (Panel) The AWS Dl.1 Code L3 dresses preheat requirements for prequalified procedures in Subsection 4.2, " Preheat and Interpass Temperature Pequirements." (If proceduras are to be qualified by test pursuant to the AWS Code, the preheat requirements specified in subsection ~ 4.2 need not be used. )

For these prequalified procedures, Table 4.2 establishes preheat requirements based on the type of material and the welding process used. For exempic, for shielded metal arc welding with low hydrogen electrodes on A36 rolled shapes and A500 Grade B structural tubing, the requirements are as follows:

Thickness (inches) Minimum Temperature Up to

3/4 Nong Over 3/4 thru l-1/2 500F Over 1-1/2 through 2-1/2 150oF Over 2-1/2 225 F Subsection NF-4611 of the ASME Code also addresses preheat requirements based on various properties, as follows:

The need for and . temperature of preheat are dependent en a number of factors, such as the-chemical analysis, degree of restraint of the .

I parts being joined, elevated temperature, physical properties and material thickness. Some practices used for preheating are given in Appendix D as a general' guide for the materials listed by P-Numbers of Section IX.. It is cautioned that

. preheating suggestedLin Appendix D does not

! necessarily ensure satisfactory completion of the welded. joint and that the preheat requirements.for individual materials!within the P-Number listing -I

may be more or less restrictive. The Welding Procedure Specification for the material being t welded shall specify the minimum preheating requirements under the welding procedure qualification requirements of Section IX [ emphasis supplied].

In short, while Appendix D of the ASME Code,Section III, provides guidance for preheat requirements (very similar to that provided in the corresponding sections of AWS), the Code states that during welding procedure qualification, the preheat requirements Which have been actually tested and produce acceptable welds are the ones to be specified in the applicable procedures.

(Baker) Qualification of procedures in accordance with the ASME Code has resulted in preheat requirements in the applicable CPSES welding procedures that in all cases either meet or exceed those preheat requirements set forth in the AWS Code.

(Panel) In sum, CASE's allegation that preheat requirements set forth in the AWS Code are not adequhtely considered at CPSES is without merit.

013. Panel, would you please describe the results of your evaluation for " Drag Angle and Work Angles" (Which limit the space allowed for the welder to function) .

A13. (Panel) Contrary to CASE's allegation, neither the AWS nor-ASMS Codes refer to, or.in any-way mention " drag angle" or

" work angle" requirements or restrictions. In its February 1, 1984, Answer to Applicants' Motion for I

m_____m_._.______m_._ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ . _ _ _ _ . _ - . _ _ _ _ _ _ _ _

< a Reconsideration, CASE provides some clarification to its concern and states in the attached Affidavit of Jack Doyle that the weld designer must take into consideration the welder's drag and work angles. For support, CASE references the Welding Handbook, Seventh Edition, Volume 2. It should be noted that this Handbook in no way states or implies that the drag angle or work angles of a welder should be an explicit design consideration. Regardless of the weld-design, the skilled welder assumes the proper drag and work angle for the job. Indeed, that very portion of the Welding Handbook referenced by CASE and attached to the Doyle Affidavit states that proper work orientation of the weld

{

rod (e.g., drag and work angle) are " automatically taken l into account" by the trained welder. In short, the welder's very basic training provides this information as well as the l

l precautions a welder has to take to make successful welds.

(Baker) Where the area Which surrounds the weld of concern is limited so as to potentially adversely impact a welder's ability to maintain proper weld orientation, as a matter of practice at CPSES welders are used Who have practiced and been tested in these configurations. For_ example, on piping where space limitations may require welding using a mirror without directly seeing the weld,- welders are trained and tested in this configuration to assure that the weld is performed correctly. Many times mock-ups of he

)

configuration (including simulating the limited space) are  !

constructed to provide precise conditions the welder will encounter. A qualification listing and matrix of the

" specially" qualified welders is maintained.

(Panel) In any event, CASE's stated concern regarding improper work angle and drag angle is that it may cause slag entrapment, porosity and undercut. Thesa defects are no different than potential concerns regarding any other weld.

Because of welder training and qualification, coupled with inspections and surveillance of the Welding Engineering Department and QA/OC, there is reasonable assurance that any problems regarding slag entrapmerit, porosity and undercut will be detected and corrected, as necessary.

In sum, CASE's allegations concerning drag angle and work angle are without merit.

014. Panel, would you please describe the results of your evaluation for " Beta Factor for Tube-to-Tube Welds" A14. (Panel) The Beta factor (the ratio of the diameters of two

?.djoining tubes) is referenced in Section 10 of AWS'Dl.1

, Code, subsection 10.12.5, 10.13.5 and Figure 10.13.5. In essence, these references provide that if the Beta Factor is greater than 1/3 for tube-to-tube (circular) connections and 1

greater than 0.8 for box (rectangular) connections, the weld procedure used most be qualified by test (the greater the l

Beta factor, the more likely that stresses at the joint will i

r e be higher). In short, where the likelihood of greater stresses is present, the Beta Factor is used in the AWS Code to indicate that qualification of a procedure by test is required. Significantly, the ASME Code requires that all weld procedures be qualified, without consideration of the likelihood of greater stresses.

In any event, in Mr. Doyle's testimony (CASE Exhibit 669, Vol. I, p. 112), he states as his concern that the Beta factor limit of 1/3 applies for shielded metal arc fillet welds used when velding trunions to pressure boundary piping. Since such a trunion would be an " integral attachment" to the piping, the AWS Code does not apply and the weld must be designed to the applicable pressure boundary subsection in ASME, i.e., NB, NC, or ND. AWS Dl.1 (as stated in paragraph 1.1.1) clearly does not apply to this case (i.e., pressure boundary piping) and Mr. Doyle's concerns are unfounded.

(Baker) It should be noted that in addition to the qualification of these procedures by testing, CPSES also has performed additional generic testing on equal sized box connections (B=1.0) to assure that penetration depth and minimum throat requirements (the major concerns for these welds) are adequate ror rectangular beam welds.

(Panel) From the foregoing, CASE's concerns regarding AWS Code requirements concerning Beta Factor are without merit. {

l

< =

17 -

Q15. Panel, would you please describe the results of your evaluation for " Lap joint requirements."

A15. (Panel) Subsection 8.8 of the AWS Dl.1 Code provides lap joint requirements for building structures. These requirements are the same as those set forth in Paragraphs XVII-2431, 2452.3(c), 2453.1, 2452.9 and 2283.l(c) of Appendix XVII of the ASME Code (mandatory to CPSES welding in conformance to ASME requirements) . (Subsection 9.10 of the AWS Dl.1 Code provides corresponding lap joint i requirements for bridges, subjected to continuous dynamic loading.)

In short, the ASME Code requirements for lap joints (with khich applicable welding at CPSES complies) are the same as related requirements in the AWS Code. Accordingly, CASE is not correct in stating that the ASME Code and applicable welding at CPSES does not elequately consider lap joint requirements as noted in the AWS Code.

016. Fanel, would you please describe the results of your evaluation for " Limitation on weld size relative to' plate thickness."

A16. (Panel) Limitations on weld size relctive to plate thickness are addressed by AWS Dl.1 Code in Subsections 2.7 (fillet welds) and 2.10 (partial penetration groove welds). These subsections basically provide that with regard to fillet and groove welds, welds to be made without qualifying the I i

i

- _ , , . , , , r --

w --

- - - -++ - * * =e , ~ * - -

applicable procedure by test shall conform to the minhnmn size requirements of Tables 2.7 and 2.10.3, respectively. l l

These requirements are identical to or less stringent than those required at CPSES by the ASME Code in Appendix XVII, Table XVII-2452.1-1.

In sum, the limitations on weld size relative to plate thickness set forth in the.AWS Code are considered in the ASME Code and factored into applicable procedares at CPSES.

Accordingly, CASE's allegation that this AWS Code provision was not adequately considered is incorrect.

-Q17. Panel, in its January 3, 1984, Memorandum, the Board requested 'that additional testimony be provided as to the requirements of both Codes ocacerning weave welding, downhill welding, preheat and cap welding. Would you please explain the specific requirements, if any, in each Code regarding these issues and state how CPSES factors these requirements into its procedures?

A17. (Panel)

1. Weave Welding Neither the AWS nor ASME Codes establish specific requirements limiting weave or oscillating pattern welding. Accordingly, there are no specific Code requirements.

i

t

• It should be noted, however, that for shielded metal arc welding (the welding of concern) bead width is l

listed as a supplementary essential variable in Scction IX of the ASME Code When impact properties are 1 l

specified, and a nonessential variable When not i I

specified. In either case, While applicable CPSES l l

welding procedures set an upper limit on bead width, the bead width can vary below that limit without impacting the procedure.

(Beker) As stated in previous testimony, CPSES welding procedures have limited bead width to four times the core diameter of the weld rod being used. Other industries Which comply with the Codes and perform qualification testa of procedures generally use bead widths in excess of four times the rod core diameter, up to and including eight times; the rod core diameter.

In sum, although there are no specific Code requirements regarding bead width (other than considering it as a supplementary essential or non-essential variable, as stated above), relevant procedures at CPSES limit the bead width to four times the rod core dimmeter.

20 - l l

i

.2. Downhill Welding (Panel) Neither the ASME nor AWS Codes exclude use of downhill or uphill welding. However, the ASME Code and the AWS Code specify that the direction of travel must be listed.

(Baker) At CPSES, Brown & Root welding procedures state that in all instances the direction of progression will a be upward. Other contractors, in a few instances, have performed qualification testing using downward progression, and downhill welding by those contractors

~

is thus permissible. In short, direction of travel is 1

considered at CPSES and is appropriately factored into welding procedures.

3. Preheat Requirements (Panel) Code requirements concerning this area and how 4 they are addressed at CPSES are discussed above in relation to CASE's concern r egarding " preheat requirements for welds on-places over 3/4 inch thick."

4. Cap Welding i

Cap welding is not terminology common to welding.

The usual' reference is a cover pass or a reinforcement-pass. There are no additional Code requirements

~

regarding cap welding; code requirements for other l

i-l l

_ , n ._ . , _ _ . . - . _ _ . . _ . - , , - . . . . . - . . _ . . . .. ,. _ . _ . . _ , , , _ . _ - _ ,

4

)

o

• welding apply equally to cap welding. Indeed, the AWS Code (1975 Revision) specifically endorses it as ,

follows:

Additional weld material to compensate for any deficiency in size shall be deposited using an electrode preferably smaller than that used for making the original weld, and preferably ,

not more than 5/32 in. (4.0 mm) in diameter. l The surfaces shs11 be cleaned thoroughly l before welding. [Section Dl.1, subsections 3.7.1].

To the extent that CASE is concerned that new weld material cannot be placed on an old weld without some adverse structural impact, CASE's concern is without merit. Neither Code provides any restrictions in this area, or even requires its consideration as an essential or non-essential variable. Such practice occurs daily when a welder takes a lunch break during a weld, or stops in the middle of a weld due to crew change or even to change a weld rod. In all such instances the welder simply follows his procedure to complete the weld. This would require actions such as cleaning the weld surface and assuring that preheat requirements, if any, are met (in most instances 60 F).

(Baker) It should be noted that CASE's concern stems from the fact that some fillet welds in the plant were found to be 1/16 inch below the minimum size specified in the ASME Code. These welds were subsequently corrected by following appropriate welding procedures

7 e

• that consisted of, among other things, cJ eaning the weld, assuring preheat requirements ware being met, welding the additional pass and obtaining a final QC visual inspection. It should be noted that in no 1

instance did any welder or QC inspector report a crack in any of the welds.

(Panel) Specifically, CASE's concerns appear to be tha~

the minimum size of the weld may have resulted in miscellaneous cracks (caused by external loading on the undersized weld), internal cracking or underbead cracking which would be aggravated when additional material is used to build up the weld.

In the first instance, the welds were designed to resist extensive and substantial seismic loading well in excess of any external loading that did occur from the time that the welds were made.until they were built up.

In this regard, it should be noted that even with undersized welds, the AWS Code states that the weld is still acceptable even if undersized 1/16 of an inch for 10 percent of the weld length (AWS Code, Sections 8.15.1.6 and 9.25.1.6). The ASME Code added,this provision to Subsection ~NF in the winter 1983 addenda.

Accordingly, CASE's speculation that miscellaneous weld t

cracks may have formed due to external loading on these welds is without merit.

- p , - e + .w- ,m-- - n, - --,, - -- __ - ,,

o

• As to CASE's concerns that internal cracking may have formed because the weld was undersized in the first instance, this is again incorrect. Indeed, it is well known and a very basic principle of welding that the primary reason for internal cracking is not an ,

I undersized pass, but rather a weld pass that is too thick. Handbooks on welding have for years stated that to prevent internal cracking you-limit the volume of the weld material deposited, not assure that more is deposited. See e.g., Omer W. Blodgett, Design of Welded Structures (1968) at p. 7.2-4 Which states that "the recommended preventive measures to eliminate internal I cracking in fillet welds is to limit the penetration and the volume of weld metal deposited per pass."

As to CASE's concerns that because the welds may have been slightly undersized there is a nubstantial problem with underbead cracking, this position is again without any supporting basis. Underbead cracking io not a problem with the mild or low carbon structural steels such as used for the bulk of the fabrication of pipe supports at CPSES, including those supports on which the undersized welding referenced by CASE occurred. These steels contain only carbon and manganese as alloying-elements (.29% maximum carbon) and do not form the martensite grain structure in the heat affected zone.of

e o i the base material that is necessary to promote underbead cracking. The high strength, low alloy steels which contain varying amounts of chromium,. vanadium, zirconium, nickel and phosphorous (and thus could result in formation of martensite in the heat affected zone) are only used for special applications at CPSES. Where these materials are used, specific welding procedures are utilized containing special preheats (300 - 400 F) and post weld heat treatment to prevent weld shrinkage and martensite formation, necessary to cause underbead cracking.

In addition to the presence of martensite and stresses caused by weld shrinkage, the presence of entrapped hydrogen is also required to develop underbead cracking. Depending on the. steel, with the elimination of either the martensite or hydrogen, underbead cracking will not occur. The hydrogen content of the weld can be reduced or eliminated through the us.e of low hydrogen electrodes. The martensite grain structure in the heat affected zone can be eliminated through the use of preheat and post weld heat treatment as specified-for.

the material in ASME III Subsection NF Article 4000 and the applicable welding procedure.

a e 1

To summarize the above, to prevent underbead j cracking, only low hydrogen type electrodes are utilized for the welding of any low or mild carbon steels or high strength low alloy structural steels. Further, the bulk of the pipe support fabrication employs carbon steels not subject to underbead cracking problems. For those special items utilizing steels which may be subject to l

underbead cracking, welding procedures are utilized I

which contain the necessary preheat or post weld heat treatment requirements to eliminate the metallurgical conditions which are necessary for underbead cracking to occur. In short, CASE's concerns regarding underbead cracking are totally without merit.

In sum, the concerns regarding cracking raised by CASE are without technical merit. In any event, it must be remembered that no cracks were identified by either the welders or QC inspectors for any of the undersized welds. If cracks had been a problem, at least some of them would have been detected and reported. In that the weld procedure contcins preheat requirements, new cracking would not be a problem. (It should be noted that preheat requ!rements make the AWS Dl.1 Code requirement to cceplete a weld in one pass unnecessary.)

4 4, ..-

1

1-t 3

In short, to the extent that CASE is concerned with 1,

j welding over previously welded joints,.such concerns are i

completely groundless.

4 r

i i

1-r h.

?

l 1

i i

i i

]

i 4

i 1-

ATTACHMENT A o *

< ' PROFESSIONAL QUALIFICATIONS OF JOHN D. STEVENSON EXPERIENCE:

PRESIDENT - MANAGING Since November 1981, Dr. Stevenson has PARTNER managed and has served as President and Senior Consultant to Stevenson &

Associates. The firm specializes in high technology consulting and forensic .

engineering associated with failure analysis of structural and mechanical systems; extreme loads; and nonlinear, dynamic, probabilistic and high temper-ature analyses.

VICE-PRESIDENT - As Vice-President, Dr..Stevenson managed GENERAL MANAGER and served as Seuicr Engineering Consul-1976 - 1981 tant to the Cleveland Offices of Woodward-Clyde Consultants and Structural Mechanics Associates specializing in areas.of high technology

, applicable to the. structural-mechanical design'and analysis of. structures, systems and components. Prior to this i

time, the consulting group he headed provided similar services as a Division of Davy-McKee Co. Dr. Stevenson also served as Corporate Manager of Engineer-l ing Quality Assurance for Davy-McKee Co.

ASSOCIATE PROFESSOR Case Wectern Reserve University, CWRU,

! 1974 - 1976 Dr. Stevenson served as-Director of a '

program in' Design for the Extreme Load Environment and held a' joint appointment in the Departments of Civil Engineering and Mechanical Design.. He.also con- '

ducted a number of seminars on Nuclear Facility Seismic, Quality Assurance, 1 Scheduling and Manpower Requirements and:

i Design.of Mechanical and Electrical Equipment and Distribution Systems including supports for Heavy Industrial Facilities.

CONSULTANT' Westinghouse Nuclear Energy Systems, l 1973 - 1974 Pittsburgh,- Pennsylvania.-

'As a Consulting Engineer for.

' Westinghouse Nuclear Energy' Systems, Dr.

~

Stevenson acted as an advisor to.the

- . .. . - , . , . . , . _.- , _ . - , . ..a...-,_- -.  :-.

, o Technical Director on the Executive Vice-President for Nuclear Power Staff.

He performed evaluations of balance of plant requirements associated with nuclear power plant design and con-structed and represented Westinghouse on a number of Industry Committees associ-ated with nuclear power.

CONSULTANT Westinghouse Water Reactor Divisi.ons, 1972 - 1973 Pittsburgh, Pennsylvania.

As an Advisory Engineer for the Westinghouse Standard Plant Project, Dr.

Stevenson acted as a consultant to the Manager of the Westinghouse Standard Planc Project. In this capacity he had i responsibility for determining interface requirements with site-related design parameters and set envelope requirements for the standard plant design. He was

, responsible for nuclear island PSAR text developments and AEC licensing require-ments associated with the standard plant layout development.

ADJUNCT PROFESSOR University of Pittsburgh, 1970 - 1972 Pittsburgh, Pennsylvania.

As a member of the Civil Engineering Facility of the University of Pittsburgh, Dr. Stevenson was particu-larly active in the areas of structural dynamic response to earthquake, tornado, missile and fluid jet effects as well as reliability and risk analysis and optimum design of structural systems.

Dr. Stevenson was responsible for the development of a graduate study program for the study of structural design and analysis for the extreme load environ-ment.

MANAGER STRUCTURAL Westinghouse PWR Systems Division, SYSTEM ENGINEERING Pittsburgh,' Pennsylvania..

1968 - 1970

.Dr. Stevenson had overall responsibility within Westinghouse for the development-and approval of structural ~ design criteria and layout used in the design of the six _ nuclear power stations .for which Westinghouse had prime design and construction responsibility ' for product i

• line management of design and develop-ment of support structures for major l nuclear components. l LEAD ENGINEER Westinghouse PWR Systems Division, 1966 - 1968 Pittsburgh, Pennsylvania. j As Lead Engineer, Dr. Stevenson was responsible for liaison with the various architect-engineer-constructor firms which performed the detailed structural design and construction of turnkey plants, and as such he was responsible for design review and approval. Dr.

Stevenson was active in representing Westinghouse structural design policy before the Atomic Energy Commission and Advisory Committee on Reactor Safe-guards.

GRAOUATE STUDENT Case Institute of Technology, Cleveland, 1963 - 1966 Ohio.

Worked towards a Ph.D. in Structures with emphasis on computer applications and riak analysis applied to structural design.

RESEARCH ENGINEER I.I.T. Research Institute, Chicago, 1962 - 1963 Illinois.

Responsibilities included integrated radiation, structural and operational analysis and minimum cost design of nuclear blast resistant underground structures.

ASSISTANT PROFESSOR 1957 - 1962 Virginia Military Institute, Lexington, Virginia.

Courses in structural design of concrete and steel structures were taught to Civil Engineering undergraduates.

John Hopkins University, Baltimore, l

' Maryland - (Part-Time) Research Assistant.

Responsibilities included report editing and research in the location, type quantity and packaging of low level solid atomic wastes.

, ,_, - ,e,

e Q '

l f FIELD ENGINEER McDowell Construction Co., Cleveland, i 1956 - 1957 Ohio.

Field Engineer responsible for technical supervision and engineering field modi-fications to construction of a Sintering Plant for U.S. Steel Corp. Youngstown Works.

Dr. Stevenson has been particul&rly active in the review and evaluation of design adequacy of structures, equipment and equip-ment supports in nuclear power plants and other industrial facilities. Particular projects where he personally performed such evaluations include the following:

Nuclear Power Plants:

Indian Point Units 2 & 3 H.B. Robinson R.E. Ginna Point 9each Dresden 2 Monticello D. C. Cook Palisades Oyster Creek Millstone South Texas Project Conn. Yankee Maine Yankee Fessenheim - France Cordoba - Argentina Milhama - Japan Other Industrial Facilities:

Tokamac Fusion Test Facility Purex Facility Hanford Rocky Flats Processing Facility Centrifuge Plant Granger Soda Ash Plant LMFBR Hercules Polyprcpalene Plant Shuichang Steel Complex Touss Oil Fired Power Station Hanford Coal Fired Power Station Addy Ferro Silicate Plant Killen Coal Fired Power Station

e o _5-EDUCATION: B.S. - Civil Engineering -

Virginia Military _ Institute, 1954 AEC Institute on Nuclear Engineering -

Purdue University, Summer 1960 M.S. - Civil Engineering -

Case Institute of Technology, 1962 Ph.D. - Civil Engineering -

Case Institute of Technology, 4 '> 6 8 PROFESSIONAL: 1. Member: American Society of Civil Engineers Chairman: Uuclear Standards Committee -

Technical Council on Codes and Standards Member: Executive Committee, Technical Council on Codes and Standards Member: Structural Division Committee on Nuclear Safety Member: Structural Division Committee on Nuclear Structures and Materials

2. Member: American Society of Mechanical Engineers Chairtr,an: Task Committee on Seismic Functional Qualification of Mechanical Components (Pumps and Valves)

Member: Subgroup'on Design of ASME BPVC-Section III-Div. 1 Nuclear Components Member: Subcommittee on Qualification of Mechanical Components in Nuclear Service

3. Member: Nuclear Standards Management i

' Board of ANSI representing ASCE

4. Member: U.S. Representative Inter-national Standards Committee SC 85/3/7 on seismic Criteria for Nuclear Plants

5. Member: AISC, American Institute of Steel Construction Committee on Specifications for Structural Steel in Safety Class Nuclear Stractures

- . .~. . . , - . - ,

.=

, o *

6. Member: U.S. Representative Inter-national Atomic Energy Agency Working Group on the Develop-ment of Seismic Design Standards

7. Registered Professional Engineer:

Virginia, Pennsylvania, and Ohio

8. Winner: Moiselff Award - ASCE, 1971 Dr. Stevenson's codes and standards activities also include being an organizing member in 1971 of the Subgroup NF which prepared the ASME Code rules on component supports. He personally was responsible for the initial draft of Appendix XVII for design of linear supports.

PUBLICATIONS INCLUDE THE FOLLOWING:

1. Stevenson, J.D., " Criteria and Design of Pressurized Water Reactor Coolant System Support Structures - State-of-the-Art," First International Conference on Structural Mechanics in Reactor Technology, Berlin, Germany, September 1971.

2. Stevenson, J.D., "Saismic Design of Small Diameter Pipe and Tubing for Nuclear Power Plants," Proc. 5th World Conference on Earthquake Engineering, Rome, June 1973.

3. Stevenson, J.D. and LaPay, W.S. " Amplification Factors to be Used in Simplified Seismic Dynamic Analysis of Piping Systems," Proc. Pressure Vessel and Piping Conference, ASME, June 1974.

4. Bergman, L.A. and Stevenson, J.D., "The Effects of Support Stiffness Upon the Response of Piping Systems," Presented at ASME National Congress on Pressure Vessels and Piping, June 1979.

5. Gorman, M. and Stevenson, J.D., " Probability of Failure of Piping Designed to Seismically Induced Emergency and Faulted Condition Limits," 5th SMIRT Conference, Berlin, Germany, August 1979.

6. Stevenson, J.D., " Nuclear Standards Applicable to the Civil-Structure Design of Nuclear Power Plants." Proceedings of Specialty Conference on Experience with the Imple' men-i tation of Construction Practices, Codes Standards, and Regulations in Construction of Power Generating Facilities, Pennsylvania State University, Seotember 1981.

1

• _7_

7. Moses, F., and Stevenson, J.D., " Reliability Based Structural Design,"-Journal of the Structural Division, ASCE, Vol. 96,-No. ST 2, Proc. Paper 7072, February 1970.

8. Stevenson, J.D. (Editor), " Proceedings of Second ASCE -t

, Speciality Conference on Structural Design of Nuclear Power Plant Facilities," New Orleans, December 1975.

9. Stevenson, J.D., and Moses, F., " Reliability Analysis of Frame Structures," Journal of the Structural Division, ASCE, Vol. 96, No. ST 11, Proc. Paper 7692, November 1970.

10. Stevenson, J .D. , and Abrams, J.I., (Editors) " Proceedings of Symposium on Structural Design of Nuclear Power Plant Facilities," University of Pittsburgh, 1972.

11. Stevenson, J . D. , " Standards - Status and Development in the Nuclear Industry," Proceedings of ASCE Specialty Conference on Design of Nuclear Plant Facilities, Boston, April 1979.

12. Stevenson, J.D., Chairman, Editing Board, Structural Analysis and Design of Nuclear Plant Facilities, ASCE Manuals and Reports on Enginaering Practice - No. 58, American Society of Civil Engineers, August 1980.

l I

I L

y--~ . . .

,,,,-,__e- , e, +-+.e

ATTACHMENT B e O Professional Qualifications of Roy E. Lorentz, Jr.

Professional Experience From 1940 -- Metallurgist with Combustion Engineering, Inc.

working on welding developments, metallography, failure analysis, nondestructive testing, material selection, production equipment development, and metallurgical applica-tion, including technical support for all groups of company including sales, engineering, production, international operations, etc.

Held succecaiva positions as Project Leader, Supervisor, Production Metallurgist, Manager Fabrication Metallurgy, Menager of Metallurgical Research and Development 1968 to 1973, and Director of C-E Power Systems Chattanooga Metal-lurgical and Materials Laboratory, until retirement from C-E in 1981.

From May 1981 -- Metallurgical Consultant to Chattanooga Concerns and the Metal Properties Council, Memberships American Welding Society, American Society for Metals, '

American Society for Testing Materials, Pressure Vessel Research Committee, ASME Boiler & Pressure Vessel Code, Metal Properties Council. Offices held include past Chairman Chattanooga Sections AWS & ASM, Past District Director AWS. Past member National Nominating Committees ,

AWS & ASM. Honors include 1962 AWS Adams Memorial Lecture-ship. 1962 Award Certificate. Active member of ASME --

Subcommittee of Welding -- Chairman of its Materials Subgroup --

and Subgroup on Plates.

Publications April 66 Metal Progress "Should Pressure Vessels Be Heat l

Treated?", 1966 Chapter 9 in Book " Combustion Engineering",

on " Materials Metallurgy", AWS Welding Handbook Chapters on "Cnromium Iron-& Steels", " Pressure. Vessels", .". Nuclear. Vessels",

" Clad Steels". AWS Journal 1957.on " Fabrication of_ Nuclear Reactor Vessels", ASTM Nondestructive Testing Symposium 1942 Book Chapter -- and many others.

Personal B.S. Metallurgical Engineering - University of Illinois -

June 1939. M.S. Metallurgical Engineering - Lehigh University -

June 1940. . Employed as Welder during college summers. Member L

Brainerd United Methodist Church and its Board of Trustees, Member Brainerd Kiwanis Club.

l

o o ATTACHMENT 1

1. In 1963 awarded certificate of ASME "In Appreciation of his Outstanding Leadership in the Development of Standards and Codes as a member of Subcommittee on Welding of the Boiler and Pressure Vessel Committee from October, 1949."

2. In 1962 awarded certificate of AWS " Adams Lecture for the year 1962 under the Title of Utilization of Quenching and Tempering for Improvement in Properties of Low Alloy Steels {

I in Heavy Thicknesses for Welded Construction and who was I selected in recognition of his attainments in the science and art of welding."

3. Co-author of American Welding Society Handbook Chapter 51

" Pressure Vessels and Boilers", Chapter 88 " Nuclear Power",

Chapter 95 " Clad Metals", of book Combustion Chapter on i

l

" Metallurgy", of Welding Research bulletin 82 (October 1962) l on " Arc Welding of Thick Cross Sections." ASME Paper 59-A-318 (January 1960) , "The Eddystone Research Story", Chapter 5 (titled " Factors Affecting Weldabiliby in Fabrication" of l I

Book -- Weldability of Steels - by Stout and Doty (1971)).

4. Presented technical talks to AWS-ANS in May, 1963, New York and in previous years to.varicus Society, University and Government organizations. (See Attachment 2).

5. Past Chairman AWS and ASM Chattanooga Section (and other offices). Past member National Nominating Committee of AWS and ASM. Past Southeastern District Representative AWS.

Member Tau Beta Pi, Sigma Xi.

, s W. e ~

e O ATTACHMENT 2 l

1. Welding Design and Fabrication Per ASME Section IX and other Codes -- Presented (For Technical Seminars, Inc.) in Albuquerque, N.M., February 1983.

2. Fabrication and Inspection of Power Plant Components --

W. R. Mc

Dearman and R. E. Lorentz,

Jr. -- Presented at INCO Power Conference 1979

3. Quenched and Tempered Heavy Section Steels -- Presented in Moscow, USSR, November 1976.

4. Matallurgical Problems and Solutions Pertaining to Nuclear Components -- Presented in Moscow, USSR, November 1976.

5. Temper Embrittlement of 2 Cr-1 Mo Steel - Panel Participa-tion, Dallas, Texas, September 1974.

6. Fabrication of Heavy Thickness, Low Alloy Steel Pressure Vessels, Presented at Petroleum Division Conference, ASME, Los Angeles, California, September 1964.

! 7. Quenched and Tempered Heavy Section Steels, by R. E. Lorentz, Jr., and W. L. Harding -- Presented at 23rd Annual Petroleum Mechanical Engineering Conference, Dallas, Texas, September 1968.

8. Evaluation of Ni-Cr-Mo Quenched and Tempered Alloy Steel For Nuclear Reactor Pressure Vessels, by J. V. Alge, U.S. Steel, R. E. Lorentz, Jr., C.E. Inc E. Landerman, West. Elect. Corp. -- Presented at ASME - 21st Annual Petroleum Mechanical Engineering Conference, New Orleans, Louisiana, September 1966.

9. Fabrication of High-Strength Heavy-Wall Pressure Vessels, by M. W. Davis and R. E. Lorentz, Jr.-- Presented at Midwest Welding Conference, Chicago, Illinois, February 1966.

10. Panel member University of Illinois short course on Welding Engineering -- Presented " Residual Stresses and Relief",

December 1960.

11. Presented technical talk at ASME National Metals Engineering Conference Workshop on "The Application of Metals in Heavy Sections - Quality Control", May 1959.

12. Presented talk to Atlanta Section of ASM on " Fabrication of Nuclear Reactor Pressure Vessels", February 1959.

0' *

13. Talk to Oak Ridge AWS Section on " Fabrication of Nuclear Reactor Pressure Vessels and Heat Exchanger Equipment",

February 1959.

14. Talk to ASME and AWS Sections of Providence, Rhode Island on " Pressure Vessels and Piping", November 1958.

! 15. Talk to AWS Northern New York Section at Albany, New York on " Fabrication Problems in the Manufacture of Reactor Vessels", November 1958.

16. Talk to Western Welding, Brazing and Heat Treating Conference at Menlo Park, California on " Fabrication of Nuclear Power Reactors and Auxiliary Equipment", March 1958.

17. With Dr. L. W. Smith, presented talk at ASME Annual Meeting, New York on " Metallurgical Design and Fabrication Problems in Pressure Vecsels for Nuclear Power", December 1957.

18. Talk to AWS National Spring Meeting in Philadelphia, Penn-sylvania on " Welding Problems in Pressure Vessels for Nuclear Reactors". published in AWS Journal, September 1957.

19. Talk to Annual Southern Metals Conference at Jacksonville, Florida, on "New Horizons in the Welding of Pressure Vessels for Nuclear Reactors", May 1957.

20. Talk to Welding Engineers Conference of the U.S. Navy, Washington, D.C. on " Fabrication of AISI Type 430 Stainless Steel Pressure Vessels." Published in Brochure of Bureau of Ships Welding Engineers Conferenen at U.S. Naval Research Laboratory, May 1956.

21. Similar talks previous years including teaching of classes.

l