ML20206S430
| ML20206S430 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 09/30/1986 |
| From: | Bamford W, Swamy S, Witt F WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| To: | |
| Shared Package | |
| ML19292F908 | List: |
| References | |
| WCAP-11257, NUDOCS 8609220219 | |
| Download: ML20206S430 (52) | |
Text
WESTINGHOUSE CLASS 3 WCAP-11257 i
ADDITIONAL INFORMATION IN SUPPORT OF THE ELIMINATION OF POSTULATED PIPE RUPTURES IN THE PRESSURIZER SURGE LINES OF SOUTH TEXAS PROJECT UNITS 1 AND 2 September 1986
, S. A.'.Swamy F..J..Witt W.'H. Bamford Verified by: E. R. Johnson ,
APPROVED: ((M
- 5. S. Pajdsamy, Manager Structufal Materials Engineering l
l WESTIhGHOUSE ELECTRIC CORPORATION NUCLEAR ENERGY SYSTEMS P.O. Box 2728 Pittsburgh, Pennsylvania 15230 860922O219 860915 PDR A
ADOCK 05000498 PDR=
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1 ACKNOWLEDGEMENT The authors wish to recognize contributions by the following individuals:
K. C. Chang s H. F. Clark, Jr.
E. R. Johnson C. C. Kim Y. S. Lee T. H. Liu A. Patterson J. F. Petsche 3 C. Y. Yang '
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TABLE OF CONTENTS Section Title Page
1.0 INTRODUCTION AND BACKGROUND
1-1 t' ,
2.0 ADDITIONAL INFORMATION 2-1 2.1 Material Characterization 2-1 2.2 History of Cracking 2-8
, 2.3 Loads 2-11 0' 2.4 Stability Analysis 2-15 2.5 Leak Rate Analysis 2-24 2.6 Fatigue Crack Growth Analysis 2-26 3.0 0,ISCUSSION AND CONCLUSIONS 3-1 APPENDIX A ARC RESPONSE TO HOUSTON LIGHTING'AND POWER COMPANY'S
, , REQUEST FOR SURGE LINE EXEMPTI0hS n
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LIST OF TABLES Table Title Page 1(a)-1 Room Temperature Mechanical Properties of the Pressurizer Surge Line Materials and Welds of the South Texas Project Units 1 and 2 Plants 2-5 1(c)-1 Fracture Toughness Properties Typical of the Surge Line 2-6 1(c)-2 Typical Tensile Properties of SA376 TP316 and Welds of Such Material for the Primary Loop 2-7 iX
LIST OF FIGURES Figure Title Page 4(b)-1 J-Internal Versus Applied Moment Using Multi-Linear Stress-Strain Representation 2-22 4(c)-1 Comparison of J Using Bi-Linear and Multi-Linear Stress-Strain Curves 2-23 5-1 Fatigue Crack Growth Scenario Leading to Wall Penetration and Leakage 2-25 6(a)-1 Reference Crack Growth Rate Law (with data) Used for Calculations of WCAP-10489 2-33 6(a)-2 Comparison of Reference Crack Growth Rate Laws for Stainless Steel at R = 0.0 2-34 6(a)-3 Comparison of Reference Crack Growth Rate Laws for Stainless Steel at R = 0.9 2 - 35 xi
l l
a SECTION
1.0 INTRODUCTION AND BACKGROUND
In February 1984 Westinghouse Electric Corporation developed for Houston Lighting and Power Company a justification for eliminating pressurizer surge line ruptures for South Texas Project Unit 1 and 2 Nuclear Power Plants. This justification was documented in Westinghouse Proprietary Class 2 Report WCAP-104B9 - Technical Bases for Eliminating Pressurizer Surtje Line Ruptures as the Structural Design Basis for South Texas Project (Auttiors: S. A. Swamy, J. C Schmertz, A. D Sane, W. T. Kaiser). WCAP-10490 wast,$eunclassified version of that report. /
Subsequently, on March 12, 1986, Houston Lighting and Power Company submitted to the U.S. Nuclear Regulatory Commission (NRC) a request for an exemption to the requirements of 10 CFR 50, Appendix A, General Design Criteria - 4 for the treatment of pressurizer surge line pipe breaks. The reports prepared by Westinghouse (WCAPs 10489 and 10490) were submitted as the technical basis for the request.
The NRC responded to the exemption request on July 10, 1986 by asking for additional information in support of the technical basis documents. The NRC letter of July 10, 1986 is given in Appendix A.
Section 2 of this report provides the responses to the six requests for additional information listed in Appendix A. Each request is listed followed by the response as an entity. Relevant conclusions are presented in Section 3.
1-1
I SECTION 2.0 ADDITIONAL INFORMATION !
2.1 Material Characterization Request 1(a): l For the base and weld metal actually in the South Texas surge line provide the mechanical properties (e.g., ultimate and yield strengths) or other significant material property, which will characterize the material.
Response to Request 1(a):
The pressurizer surge lines for South Texas Project Units 1 and 2 are identical in design. Each surge line was shop fabricated into three segments which were field welded at the plant site. Thus there are four field welds for each pressurizer line. All the pipes of both surge lines are from the same heat. Three separate sets of serial numbers are associated with each surge line. Two 90 elbows are in each surge line and are from the same heat. In each surge line there are five pipe segments, three having bends.
There are four shop welds for each surge lines. The pipes are SA376 TP316 while the elbows are SA403 WP304. The weld filler metal is Type 308.
Material properties for the pipe, elbows and welds are given in Table 1(a)-1.
l Request 1(b):
Indicate the type of weld and post weld heat treatment used to fabricate the welds in the surge line.
Response to Request 1(b):
One of the shop welds was gas tungsten arc (GTAW), two were shielded metal arc (SMAW) with GTAW root passes and one was submerged arc (SAW) with GTAW root passes. The field welds were all GTAW. All welding was performed to applicable QA procedures. There was no post weld heat treatment for the welds.
2-1
Request 1(c):
Provide a materials evaluation to demonstrate that the material stress-strain curve, J c, I and J-R curve used in the analyses are representative of the material in the surge line. This evaluation should follow the general guidelines in NUREG-1061, Vol. 3, and include a comparison of the material properties for the surge line to the material properties for test data.
Response to Request 1(c):
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ja.c.e The data in Reference 1(c)-1, 1(c)-2, and 1(c)-4 are mostly from primary loop piping material. Some typical average tensile properties for SA376 TP316 piping and welds of such material are given in Table 1(c)-2 taken from Reference 1(c)-6.
2-2 t - _ _
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Ja c e It is concluded that the properties necessary to perform elastic-plastic fracture mechanics analyses of the surge line are in evidence.
4-4 5
4 2-3 1
l References 1(c)-1 S. S. Palusamy, et al., Mechanistic Fracture Evaluation of Reactor Coolant Pipe Containing a Postulated Circumferential Through-Wall Crack, WCAP-9558, Rev. 2, May 1982, (Westinghouse Proprietary Class 2).
1(c)-2 S. S. Palusamy, Tensile and Toughness Properties of Primary Piping )
Weld Metal for Use in Mechanistic Fracture Evaluation, WCAP 9787, l May, 1981 (Westinghouse Proprietary Class 2).
1(c)-3 M. F. Kanninen, et al., " Instability Predictions of Circumferential1y Cracked 304 Stainless Steel Pipes Under Dynamic Loading," EPRI-NP-2347, April 1982.
l l
1(c)-4 W. H. Bamford, and Bush A. J., " Fracture Behavior of Stainless )
Steel," in Elastic Plastic Fracture, ASTM STP 668, 1979.
1(c)-5 W. H. Bamford, et al., The Effects of Thermal Aging on the Structural Integrity of Cast Stainless Steel Piping for Westinghouse Nuclear Steam Supply Systems, WCAO-10456, November, 1983 (Westinghouse Proprietary Class 2).
i 1(c)-6 F. J. Witt, et al., Integrity of the Primary Piping System of Westinghouse Nuclear Power Plants During Postulated Seismic Events, WCAP-9283, March 1978.
2-4
l
- TA8LE 1(a)-1 ;
ROOM TEMPERATURES MECHANICAL PROPERTIES OF THE PRESSURIZER SURGE f LINE MATERIALS AND WELDS OF THE SOUTH TEXAS PROJECT UNITS 1 AND 2 PLANTS Unit Product 0.2% Offset Ultimate Flow % Elongation % Reduction No. Form Material Yield Stress Strength Stress. per Inch , in Area 1 Pipe SA376 TP316 47,300 89,800 68,550 47.5- 62.7 1 Pipe SA376 TP316 56,200 90,200 73,200 47.5 64.6 1 Pipe SA376 TP316 46,200 90,200 68,200 48.0 64.6 1 Elbows SA403 WP304 40,100 76,700 58,350 58.0 75.0 47,000 87,400 67,200 59.0 76.5 1 Shop Weld (Typical) 308 65,000 86,000 75,500 45.0 -
l 1 Shop Weld (Electrode) 308 66,000 87,100 76,550 38.0 71.6-59.000 85,700 72,350 -
1 Field Weld 308 -
86,100a _ _ _
7 2 Pipe SA376 TP316 46,100 92,200 69,150 47.0 62.2
- 2 Pipe SA376 TP316 47,300 89,800 68,550 47.5 62.7 l 2 Pipe SA376 TP316 48,100 92,200 70,150 48.0 59.7
). 2 Elbows (same as for Unit 1) 2 Shop Weld (Typical) 308 65,000 86,000 75,500 45.0 -
Shop Weld (Electrode) 308 59,400 81,000 70,200 40.0 59.6 2 Field Weld 308 - 86,100a _ _ _
ASME Code Minimum Requirements Pipe SA376 TP316 30,0d0 75,000 52,500 Elbows SA403 WP304 30,000 75,000 52,500 Weld E308 -
80,000 .-
E308L -
75,000 -
l a Average of 14 data points from weld procedure qualification records
TABLE 1(c)-1 FRACTURE-TOUGHNESS PROPERTIES TYPICAL OF THE SURGE LINE TesgTemp. Tensile Properties (psi) Jc i
Material ( F) Yield Ultimate Flow (in-lb/in2) Tmat Reference i
21,700 65,500 43,600 a,c.e SA376 TP316 600 SA376 TP316 600 20,500 60,100 40,300 Weld 600 45,000 b 61,200 b 53,100 Weld f 600 30,000 88,800 59,400 SA376 TP304 550 - -
45,950 SA376 TP304 550 - -
45,600 SA376 TP304 600 - -
47,600 SA376 TP304 600 - -
47,600
- SA376 TP304 610 - -
47,600
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TABLE 1(c)-2 TYPICAL TENSILE PROPERTIES OF SA376 TP316 AND WELOS OF SUCH MATERIAL FOR THE PRIMARY LOOP Test Temperature Average Tensile Properties Plant Material ("F) Yield (psi). Ultimate (psi) Flow (psi)
A SA376 TP316 70 40,900 (48)a 83,200 (48) 62,050 650 23,500 (19) 67,900 (19) 45,700 E 308 Weld 70 63,900 (3) 87,600 (3) 75,750 B SA376 TP316 70 47,100 (40) 88.300 (40) 67,700 650 26,900 (22) 69,100 (25) 48,000 E 308 Weld 70 59,900 (8) 87,200 (8) 73,550 650 31,500 (1) 68,800 (1) 50,250 0
C SA376 TP316 70 46,600 (36) 87,300 (36) 66,950 650 24,200 (18) '66,800 (19) 45,500 E 308 Weld 70 61,900 (4) 85,400 (4) 73,650
- a. ( ) indicates the number of test results averaged.
l
2.2 History of Cracking Request 2:
Saction 2.0 of WCAP-10489 should include references to NUREG-0691 and NUREG-0531 reports. Evaluate the susceptibility of the surge line to
- stress corrosion cracking that is described in these NUREG's.
l Response to Request 2:
l The Westinghouse reactor ccolant system primary loop and connecting Class I lines have an operating history that demonstrates the inherent operating stability characteristics of the design. This includes a low susceptibility to cracking failure from the effects of corrosion (e.g., intergranular stress corrosion cracking). This operating history totals over 400 reactor-years,
- l. including five plants each having over 15 years of operation and 15 other plants each with over 10 years of operation.
In 1978, the United States Nuclear Regulatory Commission (USNRC) formed the second Pipe Crack Study Group. (The first Pipe Crack Study Group established in 1975 addressed cracking in boiling water reactors only.) One of the objectives of the second Pipe Crack Study Group (PCSG) was to include a review of the potential for stress corrosion cracking in Pressurized Water Reactors l (PWR's). The results of the study performed by the PCSG were presented in NUREG-0531 (Reference 2-1) entitled " Investigation and Evaluation of Stress Corrosion Cracking in Piping of Light Water Reactor Plants." In that report the PCSG stated:
"The PCSG has determined that the potential for stress-corrosion cracking in PWR primary system piping is extremely low because the ingredients that produce IGSCC are not all present. The use of hydrazine additives I and a hydrogen overpressure limit the oxygen in the coolant to very low l levels. Other impurities that might cause stress-corrosion cracking, l
1 l
l 2-8
l such as halides or caustic, are also rigidly controlled. Only for brief periods during reactor shutdown when the coolant is exposed to the air and during the subsequent startup are conditions even marginally capable of producing stress-corrosion cracking in the primary systems of PWRs.
Operating experience in PWRs supports this determination. To date, no stress-corrosion cracking has been reported in the primary piping or safe ends of any PWR."
During 1979, several instances of cracking in PWR feedwater piping led to the establishment of the third PCSG. The investigations of the PCSG reported in NUREG-0691 (Reference 2-2) further confirmed that no occurrences of IGSCC have been reported for PWR primary coolant systems.
As stated above, for the Westinghouse plants there is no history of cracking failure in the reactor coolant system loop or connecting Class 1 piping. The discussion below further qualifies the PCSG's findings.
For stress corrosion cracking (SCC) to occur in piping, the following three conditions must exist simultaneously: high tensile stresses, susceptible material, and a corrosive environment. Since some residual stresses and some degree of material susceptibility exist in any stainless steel piping, the potential for stress corrosion is minimized by properly selecting a material immune to SCC as well as preventing the occurrence ofs a corrosive environment. The material specifications consider compatibility with the system's operating environment (both internal and external) as well as other material in the system, applicable ASME Code rules, fracture toughness, welding, fabrication, and processing.
The elements of a water environment known to increase the susceptibility of austenitic stainless steel to stress corrosion are: oxygen, fluorides, chlorides, hydroxides, hydrogen peroxide, and reduced forms of sulfur (e.g.,
sulfides, sulfites, and thianates). Strict pipe cleaning standards prior to operation and careful control of water chemistry during plant operation are used to prevent the occurrence of a corrosive environment. Prior to being put 2-9
into service, the piping is cleaned internally and externally. During flushes and preoperational testing, water chemistry is controlled in accordance with written specifications. Requirements on chlorides, fluorides, conductivity, and pH are included in the acceptance criteria for the piping.
During plant operation, the reactor coolant water chemistry is monitored and.
maintained within very specific limits. Contaminant concentrations are kept below the thresholds known to be conducive to stress corrosion cracking with the major water chemistry control standards being included in the plant operating procedures as a condition for plant operation. For example, during normal pawer operation, oxygen concentration in the RCS and connecting Class i lines '.s expected to be in the ppb range by controlling charging flow chem-istry and maintaining hydrogen in the reactor coolant at specified concentra-tions. Halogen concentrations are also stringently controlled by maintaining concentrations of chlorides and fluorides within the specified limits. This is assured by controlling charging flow chemistry. Thus during plant opera-tion, the likelihood of stress corrosion cracking is minimized.
References 2-1 Investigation and Evaluation of Stress-Corrosion Cracking in Piping of Light Water Reactor Plants, NUREG-0531, U.S. Nuclear Regulatory Commission, February 1979.
2-2 Investigation and Evaluation of Cracking Incidents-in Piping in Pressurized Water Reactors, NUREG-0691, U.S. Nuclear Regulatory Commission, September 1980.
2-10
2.3 Loads '
l Request 3(a):
List individual axial loads and bending moment components used to determine the resultant axial forces and bending moments indicated on page 3-2 of WCAP-10489.
Response to Request 3(a):
- 1. For the original loads, the following lists all load components at the cr~itical location:
Load Type Axial Force (kips) Bending Moments (ft-kips)
F(x) M(y) M(z)
[
ja,c.e 1.A. Load Combination for Normal Condition (Algebraic sum of Deadweight, Thermal and Pressure):
[ = 287.14 kips F(x)
M(y) = -112.0 ft-kips M(z) = -206 ft-kips Bending Moments =
((-112)2 + (-206)2)0.5 = 234.5 ft-kips 1.B. Load Combination for Faulted Condition (absolute sum of all loads above):
- Revised from WCAP-10489 based on sign correction.
2-11
F(x) = 315.75 kips M(y) = 206.62 ft-kips M(z) = 300.54 ft-kips Bending Moments =
((206.62)2 + (300.54)2)0.5 = 364.71 ft-kips
- 2. For the 1986 revised loads, the following lists all load components at the critical location:
Load Type Axial Force (kips) Bending Moments (ft-kips)
F(x) M(y) M(z)
[
ja.c.e 2.A. Load Combination for Normal Condition (Algebraic Sum of Deadweight, Thermal and Pressure):
F(x) = 286.44 kips M(y) = -123.21 ft-kips M(z) = -255.91 ft-kips Bending Moments = ((-123.21)2 + (-255.91)2)0.5 = 284.03 ft-kips l
l 2-12
.~.- -.
4 2.B. Load Combination for Faulted Condition (absolute sum of all loads above): .
F(x) = 309.45 kips M(y) = 203.07 ft-kips
= 300.94 ft-kips M(z)
Bending Moments =
((203.07)2 + (300.94)2)0.5 = 363.05 ft-kips The 1986 revised loads tabulated above reflect current surge line pipe support configuration (as of 9/05/86). The leak-before-break evaluation for the surge line was based on the original loads. The surge line evaluations of this report are based on the 1986 revised loads. ,
l Request 3(b):
~
Provide a qualitative discussion of why a circumferential flaw in a straight pipe section is more limiting than a longitudinal flaw in an elbow or other component.
Response to Request 3(b):
The likelihood of a split in the elbows is very low because of the fact that the elbows are seamless and no flaws are actually anticipated. The prediction methods for failure in elbows are virtually the same as those for straight pipes; that is, the plastic instability predictions for straight pipes are directly applicable to elbows of the same nominal pipe size. This has been
- verified by experiments on stainless steel elbows (Reference 3(b)-1]. For the South Texas surge lines the critical flaw sizes in the longitudinal and circumferential direction based on the limit load approach are nearly equal in
, magnitude. However, the elbows are seamless and, therefore, the probability l cf any longitudinal flaw existing in the surge line is much smaller when
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compared with the circumferential direction.
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inwm.-e io 2-13
Based on the above, it is judged that circumferential flaws are more limiting than longitudinal flaws in elbows and throughout the system.
References 3(b)-1 Begley, J. A., et. al., " Crack Propagation Investigation Related to the Leak Before Break Concept for LMFBR Piping" in Proceedings, Conference on Elastic Plastic Fracture, Institution of Mechanical Engineers, London 1978.
i l 2-14 i
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tc 2.4 Stability Analysis Request 4(a):
~. How were loads combined to determine the crack opening area in the leak rate calculation? Provide justification that the method of combining loads is conservative.
Resnonse to Request 4(a):
The load combination for crac opening area is th'e normal condition combination which is defined in Reply 3(a) above. [
la,c.e This results in a conservatively low crack opening area.
Request 4(b):
The stability analysis should meet the margins on load and flaw size in Sections 5.2 (h) and (i) and factor of 10 on leakage discussed in Section 5.7 of NUREG-1061, Vol. 3. ,
Response to Request'4(b):
~
Section 5.2(h) of NUREG 1061, Vol. 3,.suggest that there should be a factor of 2 between the leakage flaw size and the critical flaw size using faulted condition loads (normal plus SSE loads). The philosophy of demonstrating acceptable margin on flaw size is a well justified technical requirement and is carried out in primary loop leak-bcfore-break analyses. However, setting a factor of at least 2 may be unrealistic in some situations, especially where the load and flaw size combinations lead to significant plasticity around the crack front. Thus a more realistic approach would be based on a [
ja,c.e The following example is considered.
2-15
l
[
ja c.e This example is judged to be acceptable, From an applications standpoint involving elastic plastic behavior it is difficult to predict the applied J using faulted loads and leak rate using normal loads as a function of flaw size. Thus to strictly adhere to the factor of 2, iterations on the flaw sizes are often required.
The objective of the leakage size flaw versus critical size flaw comparison is
[
ja,c.e l Section 5.2(1) suggests that a margin on faulted loads be calculated by ic:reasing the loads by /2. Such a factor is unrealistic for at least two reasons. First and most obvious [
ja,c.e 2-16
[
Ja,c.e While it is not knowr where the /2 originates, the application of 5.2 (1) suagests a carryover from linear elastic behavior. For linear elastic behavior, a /2 factor on load does produce a factor of 2 on J-applied. If increasing the load by /2 produces a stress state (originally below the yield stress) well into the elastic-plastic region, the factor in terms of J-applied may increase by an order of magnitude, a factor of five is not uncommon. Such increases in J-applied are judged to be unwarranted. However, a demonstrable margin on load is justified. Such margins are best expressed in terms of J, however, This suggests that a reasonably conservative requirement which adequately accounts for margin on loads is to require that
[
ja,c.e Section 5.7 of NUREG 1061, Vol.3 suggests that a through wall flaw be ocstulated of such size that the calculated leakage rate under normal operating loads is detectable with margin. For leakage a margin of 10 greater than the capability of the leakage detection system is recommended.
Regulatory Guide 1.45 specifies that each leakage detection system should be able to detect a leakage of 1 gpm in less than one hour.
l l A factor of ten in leak rate as a stand alone item is unrealistic in some 1
cases. Certainly a margin well in excess of 1 gpm must be shown but the relevance of that number it significant only in the context of the margins i demonstrated for [
l ja,c.e 2-17
An elastic plastic fracture it.achanics analysis using a lower bound multi-linear stress strain representation for the base metal is discussed in ,
the response to Request 4(c). The analysis is for the worst case location, Node 10, as noted in WCAP 10489. The results are sumarized below.
A plot of the calculated J versus applied bending moment is shown in Figure 4(b)-1. This plot is generated for a 7.5-inch postulated through-wall flaw.
The value of J corresponding to the faulted condition bending moment of 363.05 ft-kips is [' la.c.e, which is lower than the JI c of I la.c.e for the base material. The Japplied value of [
la.c.e is calculated using the base metal tensile properties.
Since the yield strength of the weld metal is significantly higher than the minimum yield strength of the base metal (See Table 1(C)-2), the Japplied value for a postulated 7.5-inch flaw in the weld will be considerably lower than [ i ]a,c.e, In addition, since the applied J value for a postulated flaw in the weld has not been'shown to be less than 750 in-lbs/in2 (f.e., lower bound JI c for welds), a tearing modulus calculation was performed using the method of (teference 4(b)-1. Tapp for the postulated 7.5-inch flaw is calculated to be
- 12. The Tmat for the weld material is conservatively estimated to be at least 60 as discussed in Request 1(c). Consequently, a marf n on local stability of at least [ la,c.e exists relative to taarirq. Therefore, the critical flaw size would be greater than 7.5-inches. The results of flaw size and leak rates are given in the following table. The leak rates are calculated using the normal operating loads of 286.44 kips axial force and 284.03 ft kips bending moment.
. Crack Length J applied Leak Rate 2 (gallons / minute)
(inches) (in-lb/in1
[. -]a,c.e 17
[ ']a,C.e 21
[ ja.c.e -
27 7.5 [ .la c.e _
m ou m . a m eio 2-18
It is noted that for the leakage flaw size [ la,c.e J-applied is a factor of over [
la,c.e. Thus adequate margin on load is demons', rated. The above results demonstrate leak-before-break for the South Texas Project pressurizer surge line.
Request 4(c):
The bilinear stress-strain curve is a nonconservative representation of the data points shown in Figure 5-11 of WCAP 10489. I'rovide justification that these curves conservatively represent the surge line material described in Item 1.
Response to Request 4(c):
[
3a,c.e 2-19
Request 4(d):
Describe the method of validating (bench marking) each computer code used in the leak. rate and fracture mechanics calculations.
Response to Request 4(d):
Within Westinghouse computer programs for use in engineering analysis, design and safety analysis must be verifiad and documented as required by division quality assurance procedures. They are placed on Configuration Control where they are available for Westinghouse general use. Computer programs en Configuration Control can only be changed by following quality assurance procedures. Summaries of computer programs used in leakc'afore-break evaluations and the verification status of each program are given talow, t
2-20
c l
i Ja.c.e ,
e a
[
' ~
y ja.c.e References -
4(b)-1 "The Application of Fracture Proof Des'gn Methods Using Tearing Instability Theory to Nuclear Piping Postulating Circumferential Through Wall Cracks," NUREG/CR-3464, September 1983.
4(d)-1 " Mechanistic Fracture Evaluation of Reactor Coolant Pipe Containing a ' -
Postulated Circumferential Through-Wall Crack," WCAP 9558, Rev. 2, ,
l Class 2.
4 2-21 Y
A ,, , , _ , ,
I 3,C,e
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, FIGURE 4(b)-1 J-INTEGRAL VERSUS APPLIED MOMENT USING MULTI LINEAR STRESS-STRAIN REPRESENTATION 2-22
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3,C,e e
h man
, 'COMPARIS0N OF J USING RI-LINEAR AND MULTI-LINEAR STRESS-STRAIN CURVES 2-23
7 l
c j 2.5 Leak Rate Analysis +T l Request 5:
l
! The crack opening area used in the leak rate computation is the average of the opening area obtained from displacements at the pipe inner and outer surfaces. It seems that the minimum area would be mure appropriate.
[
Provide justification for using the average value. -
8 l
Response to Item 5: s
[
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Ja.c.e Another reason for using the mid surface area is as follows:
l
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I ja,c.e Based on the above discussion it is judged that the mid-surface crack area is the most appropriate.
References 5-1 S. S. Palusamy et al., Mechanistic Fracture Evaluation of Reactor Coolant Pipe Containing a Postulated Circumferential ThroJgh-Wall Crack, WCAP-9558, Rev. 2. May 1982 (Westinghouse Proprietary Class 2).
2-24 l
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2.6 Fatigue Crack Growth Analysis Request 6(a):
The data cited in Reference 8-2 as the basis for the fatigue crack growth rate should be included in the report in graphical form that would 5 illustrate and justify the fatigue crack growth rate constants in equation 6-4 of WCAP-10489. These equations should represent the fatigue crack growth rate of the material characterized in Item 1.
Response to Request 6(a):
The data cited in Reference 8-2 are shown in the attached Figure 6(a)-1 taken directly from the reference. These data were obtained from a compilatica of crack growth rate results obtained in PWR environment for both Type 304 and 316 stainless steels. Associated welds were also included.
This reference crack growth rate law was used because no ASME code reference curve was available at the time. There is now a reference crack growth rate law being proposed for the ASME code, and the proposed law is documented in Reference 6(a)-1. This reference represents an exhaustive compilation of fatigue crack rate data from throughout the world for an air environment. A preliminary evaluation of the effect of PWR environment has shown that the environmental factor should be a factor of 2. Therefore, the crack growth rate equation for PWR environment is:
b dn
= C F S E AK3.30 where: C = 2.42 x 10-20 F = frequency factor (F = 1.0 for temperatures below 800*F)
S = R ratio correction (S=1.0 for R=0; S = 1+1.8R for 0<R<.8; and S = -43.35 + 57.97R for R > 0.8)
E = environmental factor (E = 2.0 for PWR environment)
AK = range of stress intensity factor, in psi /in and R is the ratio of the minimum X to the maximum K.
2-26 i
The revised reference crack growth law results in much lower fatigue crack growth rates than the reference law used in the calculations in the WCAP report, especially for high R ratio loadings. Figure 6(a)-2 shows the comparison of the old and new reference laws at an R ratio of 0.0. In this figure it may be seen that the old law is more conservative than the new law at any applied AK which exceeds 34 ksi /in. [
la.c.e Thus, on balance, the reference crack growth rate law used in WCAP 10489 is conservative relative to the proposed new reference law.
Reference 6(a)-1 James, L. A., and Jones D. P., " Fatigue Crack Growth Correlations for Austenitic Stainless Steel in Air," in Predictive Capabilities in Environmentally Assisted Cracking," ASME publication PVP-99, Dec. 1985.
Request 6(b):
The applicant will perform as realistic analysis as possible using service level A and B loads. The aspect ratio for the postulated crack in the fatigue evaluation should be 6. The aspect ratio should remain constant throughout the analysis. Unless otherwise justified the maximum allowable flaw depth is the smaller of:
(1) 60% of the wall thickness, or (2) the depth at which the plastic zone is equal to the remaining ligament.
2- 27
Response to Item 6(b):
The choice of 601G of the wall thickness, as a stand alone criterion, may be unrealistic. [
3a,c.e The basis for using plastic zone size as a criterion for fatigue crack growth is not obvious. A large plastic zone size of course suggests the potential for [ ]a,%e Plastic zone sizes are usually determined as a constant times (K/a)2 where K is the linear elastic K and o is a stress descriptive of the initiation of plasticity.
Most often a is either the yield stress or the flow stress (average of the yield and ultimate stress) depending on the reference derivation. For cyclic behavior Rice (Reference 6(b)-1) has shown the plastic zone size, rp, to be given by:
rp = hx( (6(b)-1) where o is the yield stress and AK is the range of the stress intensity factor. Knowledge of a plastic zone size, per se, does not assure that J-applied is less than J Ic-2-28
- i
Consideration of SSE during service life is an integral part of a fatigue cvaluation. Since no basis exists for determining the time of occurrence of a postulated SSE during the fatigue life, it is conservative to assume that SSE cccurs at the end of service life; hence when fatigue crack growth is greatest.- The concern is with stability and not the exceedance of JI c.
Thus [
ja.c.e are required to assure controlled and stable fatigue crack growth during service life. These criteria are sufficient to ensure large margins without [
ja,c.e is conservative. A leak-before-break analysis must establish this flaw is stable with margin under faulted conditions.
[
Ja,c.e A transient monitoring system could provide on-line data for evaluation of the conservatism in the fatigue cycles assumed. The elimination of such conservatism could form the basis for showing the surface flaw evaluation satisifies the criteria for full service life.
The criteria for fatigue crack growth to be used in the fatigue analysis of the surge line are the following:
The maximum surface flaw depth due to fatigue must satisfy the following:
[
ja,c.e l 2-29 l
L__. - -- -
[
ja.c.e Additional criteria, related to flaw lengths, are as follows:
(
1 ja.c.e Reference 6(b)-1 J. R. Rice, ASTM STP, 1967 Vol. 415, p. 247.
- Request 6(c)
l The length of the fatigue crack must be less than both:
(1) the length of tne-instability thru-wall crack at /2 (N+SSE) and l
(2) 1/2 (instability thru-wall flaw at N+SSE)
The applicant is requested to confirm that the fatigue analysis includes the items listed in b) and c), above l
I 2-30
{
\
i Response to Item 6(c):
Discussion of through wall crack length is covered in the response to Request 6(b). Margin on load is discussed in the response to Request 4(b). The approaches in those responses are applicable here and are judged to be the preferred way of dealing with crack length in fatigue evaluations.
l Response - Application of Response 6(b) and 6(c) to the South Texas Project Pressurizer Surge Line I '
f The maximum allowable preservice indication may have a depth of 0.123 in. per l
IWB-3514.3 Allowable Indication Standard for Austenitic Piping, ASME Code,Section XI - Division 1, 1983 edition. Fatigue crack growth for various initial flaw depths are given in Table 8-1 of WCAP-10489. From the table an
! initial crack [
la.c.e is conservatively chosen as a basis for examining the criteria of Responses 6(b) and 6(c). First [
la.c.e Thus Criterion 1 on flaw depth is satisfied.
For a crack having a depth of ( '
la.c.e (six times the depth) J-applied was calculated for the most severe transient. Code
! minimum base metal material properties were used in the analyses. J-applied was found to be [
la.c.e This value is well less than the J cI for thermally aged weld metal and very much less than the IJ c for the pipe (see Table 1(c)-1).
Had the tensile properties of Table 1(c)-1 been used in the J-evaluation, the margins against JI c would increase significantly especially for the weld metal. Thus Criterion 2 is met and [ e l ]a,c.e will not occur.
2 .
Finally [
la.c.e were performed using the EPRI procedure (Reference 6(c)-1). The applied .1 was found to be less than [
la.c.e and Criterion 3 of Response 6(b) is satisfied.
It is concluded that an initial part through crack will not grow in fatigue to such a degree as to lead to a through wall crack under both cyclic and
[ la.c.e Thus from the standpoint of fatigue crack growth, guillotine breaks in the pressurizar surge line should not be considered as part of the structural design basis of the South Texas Project plants.
Reference 6(c)-1 V. Kumar, M. D. German, and C. F. Shih, An Engineering Approach for Elastic-Plastic Fracture Analysis, Report No. NP-1931, Electric Power Research Institute, July 1981.
1 2-32
. _ . , . . - - - - . _ _ - - . . _ _ . _ - _ _ _ _ _ . _ _ _ . . . _ _ _ _ _ _ _ _ . . . . _ . . . , . _ . r _ __g_
10757-3 x,ff = x,,x (1-R)o.5 [MFa 6) 10 100 10-3 I I I I I Ill l l l l l ll KEY k0.2 PO.7 CF8M CAST 316 Q Q FORGED 30s OQ Z FORGED 316N O II C CF8M CAST g d
d 3 6 WELD - G U
2 10*"
I-o$ y .
als f -_
W c -
a e e
~
I 4
l
= = -
10-3 m W _
z W n #
8 u 7
=
-p=5.4 io-'2 ,w,x(,,,)o.5
.u
, 3 M
E _
kq 3* 5 5 10-5 _
a* &
_ e.
10-4 z
io-6 I I I III11 I I I I I Ill i 10 , .
100 x,9 f = Kmax(I-R)o.5 gs g FIGURE 6(a)-1 REFERENCE CRACK GROWTH RATE LAW (WITH DATA) USED FOR CALCULATIONS OF WCAP 10489 2-33
i =-8 ,
e E ~~-- = "
_ 5=. L== #} ~i . = -
iM __
~~
8 f
- _ _- .u=_=-=-ri 3:= .. #
s - -
i i:
.4* ll 5_=f:+;E TZ i-a a .
?
, == i+- 3:=M5 f ==
Ef -- -: -
~
-._~
.1-~.: f =_ =" -^~
a __.
Ft i :
2:Z
~~
m S--~ _ _. _ .
a ,
.gQ ::
a s'e
.l F '
s
===q g ---; .==;- - = = =s ==.= ). j_g ;- -
=
-se Jfb._
3 da ,4 84 w to ok3s _ _ _ - .
a
? Tvt "':
,W (4x in psiG ) E= Z_-M
, .i 1@ cgf j = 5 4 x so-it{K,0-M)'g]4 i
at R = 0. X = = AK
! / !! cax M kin %)
I ! ; ; ; ; ; ; ;;;
AK (s t a ria)
FIGURE 6(a)-2 COMPARISON OF REFERENCE CRACK GROWTH RATE LAWS 1
FOR STAINLESS STEEL AT R=0.0 l l
2-34 i
g m.-8 .. '
l -
- /
- y-e ei
- 9s M -- HM == a% -
E~ ~
==
I==
r -
[
. =
i
- ~ -~
m =n ==
.__ Le. =
crq2 == =
l #= =.1
,? ,.
~'
utn
- _.-_ _ - ..-
^
$ l l l 22m_ pud . . -
= -
t # t : -3 [ __. __ ~,f . _
-. =
. =_## .=
~
ala = 5 4 x G * { g d i- R [ p g-
{. R = o.9 .j y'=+=- /= e -
= == n (3 g ;, KsiM ) J
~
'~~ - - - ~
1 . n 1
- l l anrum S t,p-r .. ,
Im _ ,..
%- W~u:AW
, ... + -
==
- : : lu Asm--
i= u-t** =- 4- v i -
- -f=&5g *+ =
- 21 =
21
(-:: -
.-L j _ ....,
5= d= 5*M -
= [-- i-/ r
==
- _. .._.c _
- = t
- == ^~ ~
) -
y . . . _._.- -
.-= ( --
==t I
.) :
l lxPN' AK halfiI FIGURE 6(a)-3 COMPARISON OF REFERENCE CRACK GROWTH RATE LAWS FOR STAINLESS STEEL AT R=0.9 i
1 2-35
3.0 DISCUSSION AND CONCLUSIONS f The requests for additional information documented in Appendix A have been addressed in all significant aspects. Available material properties specific to the South Texas Project Units 1 and 2 pressurizer surge lines have been presented and compared with similar materials for which the fracture toughness values have been obtained experimentally. The tensile properties of the surge lin! materials are seen to be well above the ASME Section III Code minimum properties. The forged pipe and fitting materials are shown to have high fracture toughness properties, specifically, [
la,c.e Although the weld metal tensile properties are well above Code minimum values, it is subject to [
la.c.e Weld procedure and heat treatments are reviewed.
The potential for stress corrosion cracking in the pressurizer surge line is further addressed including the very positive conclusions of NUREG-0691 and NUREG-0531. It is concluded that the presence of stress corrosion cracking in the pressurizer su*ge line is most unlikely having never been observed in PWR primary system piping.
Current loads and how they are combined at the most highly stressed location in the surge line (Node 10, see WCAP-10489) are given. These loads were used for the analyses presented in this report.
Arguments are set forth to demonstrate that, in general, circumferential flaws are more limiting than longitudinal flaws. The load combination proceoure used in calculating the crack opening areas for leak rate determinations is shown to be conservative.
3-1
Significant margins on flaw size and leak rates should be demonstrated in leak-before-break evaluations. Reasonable sought after objectives are a margin of two in flaw size, and a margin of ten in leak rate. [
3a.c.e Specific margins on loads appear to be unrealistic wherein the increased loads cannot really occur and straining is promoted well into the elastic-plastic region. Alternatively,[
la c.e is recommended for the J applied as compared to the stability criteria.
A reanalysis of the highest load location (Node 10) using the 1986 revised loads demonstrated that the leak-before-break concept is applicable at the location with adequate margin.
Considering the lower bound stress-strain curve reflecting ASME Code minimum properties, the bi-linear representation of the curve used in WCAP-10489 is indeed non-conservative when compared with results using a multi-linear representation of the curve. Considering the actual representative properties of the surge line, the bi-linear representation results are probably conservative for the actual surge line load response. The elastic-plastic model of WCAP-10489 was reanalyzed used a multi-linear representation of the lower bound stress strain curve. These results formed the basis for demonstrating leak-before-break for the pressurizer surge line.
4 The computer codes used in leak-before-break analyses are under quality control procedures. Required documentation includes validation and verification.
3-2 i
)
l
[
la,c.e. the mid-surface crack area is reasonably judged to be adequately representative of the crack area at the choking plane. Supporting this, [
]a,c.e The fatigue crack growth law applied in WCAP-10489 is presented. It is shown to be generally conservative compared to a fatigue crack growth law proposed fer the ASME Code. It is recommended that the extent of fatigue crack growth be governed by [
la.c.e and monitoring are recommended for situations wherein the criteria are not met. Finally, the fatigue results of WCAP-10489 for the pressurizer surge line are shown to meet the part through flaw criteria.
In conclusion, the results presented in this report further support the conclusions of WCAP-10489. Specifically, guillotine breaks in the pressurizer surge line should not be considered as part of the design basis of the South Texas Project Units 1 and 2 Nuclear Power Plants.
3-3
APPENDIX A NRC RESPONSE TO HOUSTON LIGHTING AND POWER COMPANY'S REQUEST FOR SURGE LINE EXEMPTIONS B
~ _ - . - . . _ , _ , _ _ _ . . _ ___ - . - _ . - - , , _ . ..___._ , , _
j /' f aaes g %, UNITED STATES E ; ,,
,% NUCLEAR REGULATORY COMMISSION waspHNCTON. D. C. 20SS5
'f Sk
,o...* / 10 JUL 1986 Docket Nos.: 50-498 and 50-499 Mr. J. P. Goldbere Group Vice President - Nuclear Houston lighting and Power Company Post Office Box 1700 Houston, Texas 77001
Dear Mr. Goldberg:
SUBJECT:
SOUTH TEXAS PROJECT UNITS 1 AND 2, AL.TERNATIVE PIPE BREAK CRITERIA In letters from you dated March 12, 1986 and June 10, 1986, we received the technical basis for elimination of postulated pipe ruptures in the pressurizer surge line and in the high energy lines for auxiliary and balance of plant piping, respectively. In the March 12, 1986 letter you requested an exemption to the requirements of 10 CFR 50, Appendix A. General Design Criteria-4 for the treatment of pressurizer surge line pipe treaks. We have reviewed the information in the March 12, 1986 letter and have prepared a reauest for additional information, which is' contained in the attachment to this letter.
Similar information will be required for piping in the high energy lines for auxiliary and balance of plant piping.
In addition we request that the vendor . Westinghouse Electric Corporation, grant us permission to release system parameters, margin numbers, specific system moments and forces, references to analytical methods, leak rates and reference crack sizes, which have been designated as proprietary. This information must be included in the staff's safety evaluation supporting the published conclusions.
After the vendor has received and reviewed our request for additional information, we request a meeting between the staff and your technical personnel to facilitate our review.
~
y c n... ,'
N. Prasad Kadambi Project Manager PWR Project Directorate #5 Division of PWR licensing-A
Enclosure:
As stated cc: V. S. Noonan E. J. Sullivan, Jr.
A-1
\
l
\
Pouston Lighting & Power Company South Texas Project
(
ec:
Regional Administrator, Region IV U.S. Nuclear Regulatory Commission Dffice of Executive Director for Operations 611 Ryan Plaza Drive, Suite 2000 Arlington, Texas 76011 Mr. lanny Sinkin, Counsel for Intervenor Citizens Concerned about Nuclear Power, Inc.
Christic Institute 1324 North Capitol Street Washington, D.C. 20002 Licensing Representative Houston lighting and Power Company Suite 1309 7910 Woodmont Avenue Bethesda, Maryland 20814 e
i
)
A-2
l Mr. J. P. Golc' berg Houston Lighting and Power Company South Texas Project ec:
Brian Berwick, Esq. Resident Inspector / South Texas Assistant Attorney General Project Environmental Protection Division c/o U.S. Nuclear Regulatory Commission P. 0. Box 12548 P. O. Box 910 Capitol Station Bay City, Texas 77414 Austin, Texas 78711 Mr. Jonathan Davis Mr. J. T. Westermeir Assistant City Attorney Manager, South Texas Project City of Austin Houston I.ighting and Power Company P. 0. Box 1088 P. O. Box 1700 Austin, Texas 78767
, Pouston, Texas 77001 Ms. Pat Coy Mr. P. L. Peterson Citizens Concerned About Nuclear
- Mr. G. Pokorny Power City of Austin 5106 Casa Oro i P. O. Box 1088 San Antonio, Texas 78233 Austin, Texas 78767 Mr. Mark R. Wisenberg l Mr. J. B. Poston Manager, Nuclear Licensing 1 Mr. A. Von Rosenberg Pouston Lighting and Power Company City Public Service Boad P. O. Box 1700 P. O. Box 1771 Pcuston, Texas 77001 San Antonio, Texas 78296 Mr. Charles Halligan Jack R. Newman, Esq. Mr. Burton L, t.ex Newman & Holtzinger, P.C. Bechtel Corporation 1615 8. Street, NW P. O. Box 2166 Washington, D.C. 20036 Fouston, Texas 77001 Melbert Schwartz, Jr., Esq. Mr. E. R. Brooks Baker & Botts Mr. R. L. Range One Shell Plaza Central Power t.nd t.ight Company Houston, Texas 77002 P. O. Box 2122 Corpus Christi, Texas 78403 Mrs. Peggy Buchorn
, Executive Director Citizens for Equitable Utilities, Inc.
Route 1, Box 1684 Orazoria, Texas 77422 A-3
i I
I ATTACHMENT REQUEST FOR ADDITIONAL INFORMATION i
- 1. Material Characterization i
a) For the base and weld metal actually in the South Texas surge line provide the mechanical properties (e.g. ultimate and yield strengths) or other significant material property, which will characterize the material.
Indicate the type of weld and post weld heat treatment used to fabricate the welds in the surge line.
c) Provide a materials evaluation to demonstrate that the material stress-strain curve, Jic, and J-R curve used in the analyses are representative of the material in the surge line. This evaluation should follow the general guidelines in NUREG-1061, Vol. 3, and include a comparison, of the material properties for the surge line to the material properties for test data.
- 2. History of Cracking Section 2.0 of WCAP 10489 should include references to NUREG-0691 and NUREG 0531 reports. Evaluate the susceptibility of the surge line to stress corrosion cracking that is described in these iUREG's.
- 3. Loads a) List individual axial loads and bending moment components used to determine the resultant axial forces and bending moments indicated on page 3-2 of WCAP 10489.
b) Provide a qualitative discussion of why a circumferential flaw in a straight pipe section is more limiting than a longitudinal flaw in an elbow or other component.
A-4
I j 4. Stability Analysis k
.How were loads combined to determine the crack opening area in the leak rate calculation? Provide justification that the method of combining loads is conservative.
b) The stability analysis should meet the margins on load and flaw i size in Sections 5.2 (h) and (1) and factor of 10 on leakage discussed ,in Section 5.7 of NUREG 1061, Vol. 3.
c) The bilinear stress-strain curve is a nonconservative representation of the data points shown in Figure 5-11 of WCAP 10489. Provide justification that these curves conservatively i represent the surge line material described in item 1.
d) Describe the method of validating (bench marking) each computer code used in the leak rate and fracture mechanics calculations.
- 5. Leak Rate Analysis The crack opening area used in the leak rate computation is the average of the opening area obtained from displacements at the pipe inner and outer surfaces. It seems that the minimum area would be more appropriate. Provide justification for using the average value.
- 6. Fatigue Crack Growth Analysis a) The data cited in Reference 8-2 as the basis for the fatigue crack growth rate should be included in the report in graphical form that would illustrate and justify the fatigue crack growth rate constants in equation 8-4 of WCAP 10489. These equations should represent the fatique crack growth rate of the material characterized in item 1.
A-5
b) The applicant will perform as realistic analysis as possible using service level A and B loads. The aspect ratio for the
~ postulated crack in the fatigue evaluation should be 6. The aspect ratio should remain constant throughout the analysis.
Unless otherwise justified the maximum allowable flaw depth is the smaller of:
(1) 60% of the wall thickness, or (2) the depth at which the plastic zone is equal to the remaining ligament.
c) The length of the fatique crack must be less than both:
(1) the length of the instability thru-wall crack at 42 (N+SSE) and (2) 1/2 (instability thru-wall flaw at WSSE)
The applicant is requested to confirm that the fatigue analysis includes
+ the items listed in b) and c), above.
1 4
r A-6 I
E CHMENT 3
.N ST-HL AE /137 i PAGE / OF /
Westinghouse Water Reactor N*ademm D* sic'
. Electric Corporation Divisions eco33 Pmsbu'gtPennsylvama15230 Novembd 15, 1984 NS-NRC-84-2971 Mr. Darrell G. Eisenhut Director Division of Licensing U.S. Nuclear Regulatory Comission
- 7920 Norfolk Avenue Bethesda, MD 20014
Subject:
Release of Proprietary Information
Dear Mr. Eisenhut:
Over the past few months there have been several discussions among Westinghouse and NRC technical / legal staffs regarding the release of infonnation considered by Westinghouse to be proprietary. This information is contained in Westinghouse ~opical Reports (WCAP's) related to mechanistic fracture mechanics analyses of RCS primary loop piping and large Class 1 piping attached to the RCS. A listing of these reports by plant, proprietary l class, piping system, and Docket Number is contained in the attachment. These reports are used as the technical bases for NRC approval to eliminate previously postulated pipe breaks from the structural design basis of certain Westinghouse plants.
I Af ter careful review'of this information, Westinghouse maintains that it is l proprietary as defined in the affidavits submitted to the NRC with the applicable Westinghouse Topical Reports. However, the NRR Staff has requested Westinghouse to release portions of this information in order to support conclusions reached by them in specific plant safety evaluation reports. In l light of the potential regulatory impact associated with NRC approval of l specific utility requests to eliminate previously postulated pipe breaks and the potential safety and economic benefits to utilities, Westinghouse hereby l agrees to permit the Staff to release certain information considered by Westinghouse to be proprietary.
The proprietary information which Westinghouse agrees to release is as follows:
- l. Plant parameters (operating temperatures, operating pressures, pipe dimensions)
- 2. Margin numbers (e.g., a factor of 10 on a specific criteria)
- 3. Specific plant moments and forces
- 4. Reference to the analytical methods used (i.e., limit load)
. 5. Leak rates --
- 6. Reference crack size QtfIMptR(7-
\
(
ATTACHMENT .3 ST HL.AE M37 Mr. D. G. Eisenhut PAGE A OF t/
November 15, 1984 a NS-NRC-84-4977 The remainder of the information identified as proprietary in the attached list of Westinghouse Topical Reports should continue to be treated as proprietary information.
I believe that the above stated Westinghouse position should resolve your l concerns. If you have any additional questions or this matter, please contact me at 412-374-4868 or Mr. R. A. Wiesemann at 412-374-5132.
Very truly yours, WESTINGHOUSE ELECTRIC CORPORATION
- E. P. Rahe, r., Manager Wuclear Saf y ,
JJM/anj Attachment
, cc: B. D. Liaw W. V. Johnston R. Vollmer 4
1 0170n/JJM/11-84 L
ATTACHMENT 3 -l ST.HL AE /737 PAGE3 0F V
' LIST' F WESTINGHOUSE TOPICAL REPORTS (Page 1 of 2).
Plant Plant WCAP Class Pipina System Dockets Comanche Peak 1&2 10527 Proprietary RCS 50-445 10528 Non-Proprietary .' 50-446 Catawba 1&2 10546 Proprietary RCS 50-413 10547 Non-Proprietary 50-414 Vogtle 1&2 10551 Proprietary- RCS 50-424
. 10552 hen-Proprietary 50-425 Byron 1&2 10553 Proprietary RCS 50-454 Braidwood 1&2 10554 Non-Proprietary 50-455 50-456 50-457 .
i Beaver Valley 2 10565 Proprietary RCS 50-412
! 10564 Non-Proprietary South Texas 1&2 '10559 Proprietary RCS 50-498 10560 Non-Proprietary 50-499 Seabrook 1&2 10557 Proprietary RCS 50-443 i 10566 Non-Proprietary 50-444 Millstone 3 10587 Proprietary RCS 50-423 10586 Non-Proprietary i
McGuire 1&2 10585 Proprietary RCS 50-369 l 10584 Non-Proprietary 50-370 SNUPPS Callaway & 10691 Proprietary RCS 50-483 Wolf Creek 10690 Non-Proprietary 50-482 l
l Prairie Island 1 10639 Proprietary RCS 50-282 i 10640 Non-Proprietary Shearon Harris 1 10699 Proprietary RCS 50-400 10700 Non-Proprietary South Texas 1&2 10489 Proprietary Surge Line 50-496 l 10490 Non-Proprietary 50-499 l
Catawba 1&2 10487 Proprietary Surge Line 50-413 10488 Non-Proprietary 50-414 l
l Catawba 1&2 10537 Proprietary Accumulator Line 50-413 10538 'Non-Proprietary 50-414 l
1 l
t
! 0170n/JJM/11-84
)
ATTACHMENT >
. * . ST HL AE- /757 PAGE v OF t/ .- -
. LIST 5FWESTINGHOUSETOPICALREPORTS (Page 2 of 2)
Plant Plant WCAP Class Pipina System Dockets Catawba 1&2 & 10577 Proprietary RHR Line ,50-413 McGuire 1&2 10576 Non-Proprietary 50-41t.
50-369 50-370 McGuire 1&2 10601 Proprietary Accumulator Line 50-369 10600 Non-Proprietary 50-370 McGuire 1&2 10607 Proprietary Surge Line 50-369 10606 Non-Proprietary 50-370 i
0170n/JJM/11-84
. _ _ - - . - _ . . . - . - - _ _ - -