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Rev 1 to Large Bore Pipe Stress & Pipe Support Generic Issues Rept
	ML20236K771
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Site:	Comanche Peak
Issue date:	07/24/1987
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TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION rm TUELECTRIC LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT REVISION 1

JULY 24,1987 STONE & WEBSTER

?R 1888R 8?888 b PDR A

LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT, REVISION 1 DESCRIPTION OF CHANGE l

Revision 1 All major changes to the text are as noted with a vertical line in the righthand margin. Minor editorial changes are not highlighted.

The following changes were made through-out the text where appropriate and are not highlighted:

1.

References to NRC have been changed to NRC Staff 2.

Updated references made to CPPP-7 from Revision 2 to Revision 3 l

3.

Referenced the applicable sections of CPPP-7, Revi-sion 3, in lieu of project memoranda where the pre-viously referenced memoranda have been incorporated in CPPP-7, Revision 3.

The detailed changes made in this revision are as follows:

i Section 2.0 Page 5 Clarified the relationship between CYGNA and TU Electric.

Pages 5&6 Added last two paragraphs regarding changes to appendixes and the purpose of Revision 1 of the Generic Issues Report.

Section 5.0 Page 6 Revised the discussion of the index of appendixes.

Section 6.0 Pages 7&8 Listed additional abbreviations used in the text.

Appendix A 1.2 Added reference to CYGNA RIL 3.1 Clarified use of safety factors Incorporated SWEC-CAP review of Richmond Insert Test Procedure Incorporated RLCA Reports on Richmond inserts interaction', long tube steel members, and Rich-mond Insert tube modeling 3.2 Added Richmond insert spacing program Revised number of stress cycles to'7000 4.0 Added references 5.0 Incorporated limits on long tube steel Appendix B 1.1.2 Added discussion on pipe local stress 1.3.4 Added reference to CYGNA RIL 2.2 Added discussion on pipe local stress 3.1.2 Deleted reference to cinched U-bolts 4.0 Added reference 5.0 Deleted reference.to cinched U-bolts (formerly Section 5.3) l 0348-1545405-HC4 1

1 l

l l

l Appendix-C 3.3 Revised equations' to reflect loads due to l

displacements Added. fbuckling stress check to discussion on stability l

3. 4' Revised definiti'ons to reflect loads due to displacements, revised to include motion be-tween walls for OBE and SSE Revised. discussion.on support flexibility

' Clarified definition of thermal load l

3.5 Revised ~ equations to reflect loads due to displacements 5.0 Added reference to PM-039 Appendix D

_ 1.0 Added reference to CYGNA RIL 3.2 Updated modifications of unstable supports to t

reflect the elimination of cinched U-bolts 4.0 Added reference Appendix'E 1.0 Added reference to CYGNA RIL 3.1

-Added-reference to SWEC Generic Stiffness Report 3.1.1 Revised paragraph title and verbage 3.2 Clarified examples of-components in the support assembly 4.0 Added. references Appendix F 4 '. 0 Added references

-Appendix G 1.0 Added reference to CYGNA RIL and additional background to account. for this issue. being reopened 4.0 Added reference Appendix H 3.1.1 Added reference to AWS code 4' 5 Revised reference Appendix I 3.0 Updated to include' Code Case N71-15 Deleted discussion on ASME Code Committee position 4.7 Added reference 5.0 Updated to include Code Case N71-15 Appendix J 1.1 Clarified basis for section propertie.s 1.2 Clarified statement on effective throat 3.1 Clarified basis for section properties 3.2 Revised discussion on effective throat of flare bevel welds to include SWEC survey 4.5 Added reference 5.2 Added PM-140 for SWEC survey t

0348-1545405-HC4 2

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/

4 o

Appendix K 3.0 Added statement for elimination of cinched l

U-bolts

'r Deleted remainder of section 5.0 Revised to reflect the elimination of cinched U-bolts Appendix L 3.1.2.1 Clarified riser clamp allowables 3.1.2.2 Clarified riser clamp allowables Added 'iscussion on shear load sharing d

Appendix M 3.0 4.8 Added reference 5.0 Added discussion on shear load sharing Clarified incorporation of ASME summer addenda Appendix N 1.3 Added reference to CYGNA RIL 3.1 Clarified ute of damping values Clarified use of Code Case N411 damping values 3.2 Updated to Rev. 3 of CPPP-7 4.0 Added References 5.1 Revised to include Code Case N411 damping values Appendix 0 3.0 Clarified types of support mass 5.1 Clarified inclusion of support mass in pipe stress analysis Appendix P 3.0 Deleted statement that stress and support anal-ysis are performed at the same location 1

Appendix Q 1.0 Added reference to CYGNA RIL 4,2 Added reference Appendix R 1.0 Added reference to CYGNA RIL 4.4 Added reference 5.2 Updated level and version of NUPIPE-SW Appendix S 3.1 Revised section of NUREG guide Appendix T 4.0 Revised references Appendix U 3.1 Clarified method for local stress evaluation Added items 9 and 10 to list for local stress evaluations Added appropriate code reference to each item 4.0 Added refere:.ces Appendix W 3.1 Deleted paragraph on cinched U-bolts 3.3 Added statement for the elimination of cinched U-bolts 3.4 Deleted section on SA-36 material in friction connections Revised number of cycles for fatigue analysis 0348-1545405-HC4 3

3.5 Clarified factor of safety Deleted paragraph on cinched U-bolts 4.7 Added reference 5.2 Added statement for the elimination of cinched U-bolts.

Deleted reference to cinched U-bolt tests and methodology.

I 5.3 Revised number of cycles for fatigue analysis Appendix X 5.0 Added statement for the elimination of cinched U-bolts Appendix Y 1.0 Added reference to CYGNA RIL Added CYGNA's concern on the modeling of flexi-ble valves 2.3 Added flexible valve consideration 3.1 '

Revised discussion on flow distribution 3.4 Added flexible valye consideration 4.0 Added references 5.1 Revised discussion on flow distribution 5.3 Clarified the recipients of valve acceleration and support load information 5.4 Added procedure for modeling of flexible valves Appendix Z 1.0 Added reference to CYGNA RIL Added additional CYGNA pipe modeling. concern 2.0 Deleted statement regarding effect on safety 4.3 Added reference Appendix AA 1.0 Added reference to CYGNA RIL 3.1 Added statement for the elimination of minimum weld size requirement 3.2 Revised paragraph on weld subsurface cracking 3.3 Revised paragraph on fillet weld cracking 3.4 Added statement to include eccentricities in weld design 3.6 Added statement to include the entire shear force in weld design 3.7 Added reference to applicable section of CPPP-7 4.0 Added references Appendix BB 1.0 Added reference to CYGNA RIL 2.0 Revised load transmittal to SWEC-CAP 3.0 Revised load transmittal to SWEC-CAP 3.2.3 Added SWEC bolt edge distance study 3.2.4 Revised to SWEC-CAP 3.2.5 Revised to SWEC-CAP 4.0 Added references 5.2 Revised to SWEC-CAP 5.3 Added statement on anchor bolt edge distance 5.5 Added statement for development of SWEC-CAP program for anchorage 0348-1545405-HC4 4

Appendix DD 1.0 Added reference to CYGNA RIL 2.2 Clarified statement for component qualif. cation 2.5 Added statement for material compatibility of nuts and bolts 3.2 Added caveat for qualification of U-bolts used as two-way restraints 3.3 Clarified reinspection of pipe supports under the IIVP 3.4 Added procedure for evaluation of A563 Grade A nuts with A193 threaded rods 4.3 Added reference 5.3 Added caveat for qualification of U-bolts used as two-way restraints Appendix FF 2.0 Updated to include review of CPRT Results Reports 3.0 Updated to include review of CPRT Results Reports 4.0 Added references 5.0 Added conclusions from review of CPRT Results Reports Appendix GG 3.1 Added discussion for HVP 4.3 Added reference 0348-1545405-HC4 5

Texas Utilities Electric Company Status Date 07/24/87 J.0.No. 15454/15616 Job Book Q5.12 Page 1 of 2

_INDEX OF GENERIC ISSUES COMANCHE PEAK STEAM ELECTRIC STATION Rev.

Date of Document Title No.

Issue-1 REPORT REPORT ON SWEC'S EVALUATION 1

07/24/87 AND RESOLUTION OF GENERIC ISSUES APPENDIX A RICHMOND INSERTS 1

07/24/87 APPENDIX B LOCAL STRESS IN PIPING 1

07/24/87 APPENDIX C WALL-TO-WALL AND FLOOR-TO-1 07/24/87 FLOOR SUPPORTS APPENDIX D PIPE SUPPORT / SYSTEM STABILITY 1

07/24/87 APPENDIX E PIPE SUPPORT GENERIC STIFFNESS 1 07/24/87 APPENDIX F UNCINCHED U-BOLT ACTING AS A 1

07/24/87 TWO-WAY RESTRAINT APPENDIX G FRICTION FORCES 1

07/24/87 APPENDIX H AWS VS. ASME CODE PROVISIONS 1

07/24/87 APPENDIX I A500, GRADE B, TUBE STEEL 1

07/24/87 APPENDIX J TUBE STEEL SECTION PROPERTIES 1

07/24/87 APPENDIX K U-BOLT CINCHING 1

07/24/87 APPENDIX L AXIAL / ROTATIONAL RESTRAINTS 1

07/24/87 APPENDIX M BOLT HOLE. GAP 1

07/24/87 APPENDIX N OBE/SSE - DAMPING 1

07/24/87 APPENDIX 0 SUPPORT MASS IN PIPING 1

07/24/87 ANALYSIS APPENDIX P ITERATIVE DESIGN 1

07/24/87 0660ZZ-1545405-HC4

Texas Utilities Electric Company Status Date 07/24/87 J.O.No. 15454/15616 Job Book Q5.12 Page 2 of 2 i

Rev.

Date of Document Title No.

Issue APPENDIX Q MASS POINT SPACING 1

07/24/87 APPENDIX R HIGH-FREQUENCY MASS 1

07/24/87 PARTICIPATION APPENDIX S FLUID TRANSIENTS 1

07/24/87 APPENDIX T SEISMIC EXCITATION OF PIPE 1

07/24/87 SUPPORT MASS APPENDIX U LOCAL STRESS IN PIPE SUPPORT 1

07/24/87 MEMBERS APPENDIX V SAFETY FACTORS 1

07/24/87 APPENDIX W A36 AND A307 STEEL 1

07/24/87 APPENDIX X U-BOLT TWISTING 1

07/24/87 APPENDIX Y VALVE MODELING/ QUALIFICATION 1

07/24/87 APPENDIX Z PIPING MODELING 1

07/24/87 APPENDIX AA WELDING 1

07/24/87 APPENDIX BB ANCHOR BOLTS 1

07/24/87 APPENDIX CC STRUT / SNUBBER ANGULARITY I

07/24/87 l

APPENDIX DD COMPONENT QUALIFICATION 1

07/24/87 APPENDIX EE SSER-8 REVIEW 1

07/24/87 APPENDIX FF SSER-10 REVIEW 1

07/24/87

, APPENDIX GG SSER-11 REVIEW 1

07/24/87 0660ZZ-1545405-HC4

J.O.No. 15454.05-11H REVISION 1 DATE:

07/24/87 l

TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION UNITS 1 AND 2 STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT 5

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P. Dunlop R. R. Wrucke Engineering Manager Project Engineer - Unit 1 2

44a C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager -

Production A. W. Chan

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Assistant Project Manager -

Technical NG R. P. Klause l

Project Manager 1

TABLE OF CONTENTS Payg TITLE PAGE 1

TABLE OF CONTENTS 2

LIST OF GENERIC ISSUES 3-4

1.0 INTRODUCTION

5 2.0 GENERIC ISSUES - SCOPE 5

3.0 ISSUE RESOLUTION PROCESS 6

4.0 REPORT ORGANIZATION 6

5.0 ISSUE PROCESS 6

6.0 ABBREVIATIONS 7-8 Atta ctunent 1 TITLE PAGE - APPENDIXES 9

0660-1545405-HC4 2

LIST OF GENERIC ISSUES Appendix Title A

RICHMOND INSERTS B

LOCAL STRESS IN PIPING C

WALL-TO-WALL AND FLOOR-TO-FLOOR SUPPORTS D

PIPE SUPPORT / SYSTEM STABILITY E

PIPE SUPPORT GENERIC STIFFNESS F

UNCINCHED U-BOLT ACTING AS A TWO-WAY RESTRAINT G

FRICTION FORCES H

AWS VS. ASME CODE PROVISIONS I

A500, GRADE B, TUBE STEEL J

TUBE STEEL SECTION PROPERTIES K

U-BOLT CINCHING L

AXIAL, ROTATIONAL, AND TRAPEZE-TYPE RESTRAINTS M

BOLT HOLE GAPS N

OBE/SSE - DAMPING 0

SUPPORT MASS IN PIPING ANALYSIS P

ITERATIVE DESIGN Q

MASS POINT SPACING R

HIGH-FREQUENCY MASS PARTICIPATION S

FLUID TRANSIENTS T

SEISMIC EXCITATION OF PIPE SUPPORT MASS U

LOCAL STRESS IN PIPE SUPPORT MEMBERS V

SAFETY FACTORS W

A36 AND A307 STEEL 0660-1545405-HC4 3

Appendix Title X

U-BOLT TWISTING Y

VALVE MODELING/ QUALIFICATION Z

PIPING MODELING AA WELDING BB ANCHOR BOLTS CC STRUT / SNUBBER ANGULARITY DD COMPONENT QUALIFICATION EE SSER-8 REVIEW FF SSER-10 REVIEW GG SSER-11 REVIEW 1

0660-1545405-HC4 4

1.0 INTRODUCTION

Stone & Webster Engineering Corporation (SWEC) has been retained by Texas Utilities Generating Company (TU Electric) to requalify the ASME Class 2 and 3 piping and ASME Class 1, 2, and 3 pipe supports for Comanche Peak Steam Electric Station (CPSES) - Units 1 and 2.

As part of SWEC's scope, SWEC is required to develop administrative and technical procedures to guide the work.

.SWEC has identified the concerns, allegations, and eva'uationc raised by l

groups external to the TU Electric / Comanche Peak Project organization that affect the pipe stress and pipe supports requalification effort.

These concerns, allegations, and evaluations, classified as Generic is-sues, address technical methods and procedures as well as interface ac-tivities among design organizations and between design organizations and vendors.

SWEC deemed it necessary and prudent to address these concerns in the early stages of the project, to ensure that the affected project procedures are complete and that all issues are properly resolved.

This report and its appendixes summarize SWEC's resolution of each issue and identify specific sections of the pertinent project procedures that incorporate the resolutions.

2.0 GENERIC ISSUES - SCOPE The generic issues discussed in this report originated from outside the TU Electric / Project organization. They were identified by Citizens Asso-ciation for Sound Energy (CASE), an intervenor organization; CYGNA, a consulting firm, originally contracted by the applicant to perform pro-ject review for the Independent Assessment Program (IAP) that was re-quested by the NRC Staff; the NRC Sta f f; and consultants to the NRC Staff, through staff reviews and NRC Staff Special Inspection Team (SIT) reviews.

These issues have been previously identified and communicated to the ASLB and/or NRC Staff in hearings, discussions, or document submittals and have been documented in correspondence, reports, supplemental safety evaluation reports (SSERS), and affidavits and transcripts of testimony before the ASLB or NRC Staff.

TERA has been retained by TU Electric to review the above documentation

~.

and to ensure that all issues / concerns are clearly identified and resolved.

However, in this report, SWEC will evaluate and address only those tech-nical and design interface issues that affect the pipe stress and pipe support requalification program.

The appendixes have been revised as noted to reflect SWEC progress in i

issue resolutions, and to update the resolution sections to current revi-e sions of project procedures and project memoranda.

Revision 1 is the final revision of this Generic Issues Report.

Revi-sions to the information in this report and final issue resolutions will 0660-1545405-HC4 5

(

l l

l be provided in Appendix A and B of the Large Bore Piping and Pipe Supports Project Status Report.

3.0 ISSUE RESOLUTION AND IMPLEMENTATION PROCESSES 3.1 For each issue that affects the SWEC requalification effort, SWEC reviewed the associated documentation to gain an understanding of the background.

SWEC then summarized its understanding of the issue.

3.2 With the issue thus summarized, SWEC developed an action plan to resolve the issue. This action plan was then executed.

3.3 The resolutions are implemented in appropriate SWEC project proce-dures for the CPSES requalification program.

Compliance to these procedures is ensured by the SWEC Corporate Quality Assurance pro-gram. Adequate implementation of resolutions for the generic issues is a subtask within SWEC's management plan for project quality in CPPP-1.

4.0 REPORT ORGANIZATION The main report body contains an overview of the issue background, scope, list of generic issues, resolution, and implementation processes for the requalification program.

A separate series of appendixes is issued in conjunction with this re-port.

Each appendix serves as a report on the issue resolution process for the specific titled issue.

5.0 ISSUE PROCESS The main report body and each apper. dix will be issued separately, each with its own title and signature page. An index of appendixes will also be included.

The title page of each appendix will resemble Attachment I and will con-tain the signatures of the Project Engineer - Unit 1, Project Engineer -

Unit 2, and Assistant Project Manager - Production, the Assistant Project Manager -

the Project Manager, and the Chief Engineer -Engineering Me-chanics Division.

muss 0660-1545405-HC4 6

6.0 ABBREVIATIONS The following abbreviations are used throughout the report and its appendixes:

ACI:

American Concrete Institute AISC:

American Institute of Steel Construction l

ASLB:

Atomic Safety Licensing Board ASME:

American Society of Mechanical Engineers, Boiler and Pres-sure Vessel Code,Section III, Division 1, Nuclear Power Plant Components ASTH:

American Society of Testing Materials CAP:

Corrective Action Program l

CASE:

Citizens Association for Sound Energy CHOC:

Cherry Hill Operations Center l

CMC:

Component Modification Card CPPP-1:

Comanche Peak Project Procedure No. 1, Management Plan for Project Quality CPPP-6:

Comanche Peak Project Procedure No. 6, Pipe Stress / Support Requalification Procedure - Unit No. 1 CPPP-7:

Comanche Peak Project Procedure No. 7, Design Criteria for Pipe Stress and Pipe Supports CPPP-9:

Comanche Peak Project Procedure No. 9, Pipe Stress / Support As-Built Procedure - Unit No. 2 CPPP-10 Comanche Peak Project Procedure No. 10, Procedure for Doc-umented Review of Plant Operating Mode Conditions CPSES:

Comanche Peak Steam Electric Station CYGNA:

CYGNA Energy Services DCA:

Design Change Authorization l

f'c:

Concrete compressive strength (psi)

Fs:

Factor of safety FX:

Force along the X axis FY:

Force along the Y axis l

FZ:

Force along the Z axis l

ksi:

Kips per square inch l

MX:

Moment about the X axis MY:

Moment about the Y axis MZ:

Moment about the Z axis NPSI:

NPS Industries Incorporated NRC :

United States Nuclear Regulatory Commission l

NUPIPE-SW SWEC Piping Analysis Computer Program PSE:

Pipe Support Engineering Group (TU Electric) l R:

Tube Steel Corner Curve Radius RE:

Richmond Inserts RIL:

CYGNA Review Issues List l

RLCA:

Robert Cloud Associates R:

Tube Steel Corner Tangent Radius l

SkT:

Special Investigation Team (NRC Staff)

SSER:

Supplemental Safety Evaluation Report SWEC:

Stone & Webster Engineering Corporation t:

Tube Steel Wall Thickness t :

Weld Effective Throat

[

TfRA:

TERA Corporation TES:

Teledyne Engineering Services 0660-1545405-HC4 7

TRT:

Comanche Peak Technical Review Team (NRC Staff)

TU Elec-Generating Division of Texas Utilities Electric Company, tric formerly Texas Utilities Generating Company (TUGCO) q l

a 0660-1545405-HC4 8

I 1

4

J.O.No. 15454.05-11H REVISION:

1 DATE:

07/24/87 ATTACHMENT 1 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX _:

(Title)

D. C. Foster R. R. Wrucke Chief Engineer -

Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager -

Production A. W-Chan Assistant Project Manager -

R. P. Klause Project Manager 0660-l545405-HC4 9

..J.0.No.

15454,05-11H REVISION 1 DATE:

07/24/87 TU ELECTRIC COMANCHE PEAK STE!.M EIICTRIC STATION REPORT ON STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT ADPENDIX A: RICHMOND INSERTS dI f D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division I

C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager -

Production

.h A. W. Chan Assistant Project Manager -

l Technical.

k 4 o:

R. P.'ltlause Project Manager r

4 8

e

__._____._.______________d

l APPENDIX A - RICHMOND INSERTS

1.0 Background

1.1 There are seven interrelated CASE issues regarding the use of Rich-mond inserts:

1) TU Electric used a safety factor of two for Rich-mond insert designs instead of the manufacturer's recommended safety factor of three; 2) TU Electric has insuf ficient test data to lower the safety factor; 3) TU Electric used Richmond inserts in conjunc-tion with tLoe steel without considering the effect of the tube steel member's torsion on the bolt; 4) the method TU Electric used to analyze the connections may be inadequate, namely, whether to consider them as pinned or fixed ends; 5) the bolts used in the con-nection are subject to bending, and the code does not specify an interaction equation in order to combine bending with the bolt's tension and shear reactions; 6) the holes made in the connections are oversized, and therefore the sharing of shear loads cannot be assumed to be equal for all of the bolts; and 7) thermal expansion of long tube steel members anchored by two or more inserts was not considered.

1.2 The issue on the fatigue life of the threaded rod / bolt was raised by the NRC Staff.

The issue of allowable spacing of Richmond in-serts was raised by CYGNA, as stated in Issue 8 of Reference 4.17.

1.3 TU Electric contended that the safety factor of 2 is acceptable since the CPSES's design concrete strength is considerably stronger than the concrete strength used in the manufacturer's tests.

To demonstrate the ac,ceptability of this safety factor, TU Electric conducted several tests of its own on Richmond inserts.

Allegations 3 through 5 can be grouped. The fact that bolt bending is not addressed in any original design criteria has led TU Electric to assign RLCA to review, evaluate, ar.d recommend a Richmond insert bolt interaction equation.

TU Electric is committed to modify the connections that are single tube steel members subject to torsion and/or suear, and any inserts that have an interaction ratio of greater than 1.0.

Finally, regarding the issue of the sharing of shear loads, TU Elec-tric demonstrated that considerable margin exists between the de-flection of one bolt before bringing the remaining bolts into action and the deflection that would cause bolt failure (Reference 4.18).

2.0 SjEC's Understanding of the Issues A procedure, which incorporates the proper safety factor, modeling inter-action, and spacing requirements to evaluate and modify (if necessary) the Richmond insert designs, including designs used in conjunction with tube steel, is needed.

0660A-1545405-HC4 A-1

3.0 SWEC Action Plan To Resolve the Issue 3.1 SWEC established the insert allowable loads based on the average failure value of insert' specimens as reported in the March 30, 1983 and April 19, 1984, TU Electric Test Reports (Reference 4.2) and a safety factor of 3 for normal, upset, and emergency conditions and a safety factor of 2 for faulted condition.

This failure value is defined as the " tested failure value" multiplied by the square root of the ratio of the CPSES design concrete strength of 4000 psi and the concrete test strength.

SWEC-CAP verified that the tests were representative of CPSES Rich-mond insert / concrete installations and that the tests were performed in accordance with ASTM Standard E488-76.

SWEC has also established the tube steel to bolt load transfer mechanism for shear and torsion loads (with respect to the tube steel) and has developed a conservative design methodology for eval-uating these connections.

RLCA performed an independent analysis of the tube steel to bolt load transfer mechanism and confirmed that SWEC's methodology is appropriate (Reference 4.13).

l The SWEC model simulates a member with bolt properties in the STRUDL computer program to connect the center of tube steel to the face of concrete.

All forces and moments at the support joints are fixed except for the bolt's torsional moment. The force and moment reac-tions are first used directly in the interaction equation recom-mended by RLCA for qualifying the bolts and are later converted to tension for evaluating the inserts.

This interaction equation is documented by both RLCA (Reference 4.14) and SWEC (Reference 4.16).

This method of analysis is a conservative means of transferring shear and torsion loads from the tube steel to the bolts Single l

tube steel members subject to torsion have outriggers in:telled at the connections to eliminate the moment on the bolt.

The shear loads are assumed to be shared by all bolts.

However, during final reconciliation, these designs will be reviewed to confirm that unequal shear load sharing is not a concern.

The effects of thermal expansion on long tube steel members anchored by two or more inserts has been evaluated by RLCA.in Reference 4.15, and limits on tube steel length have been established.

3.2 Attachment 4-5 of CPPP-7, Revision 3, specifies spacing requirements and the effect of reduced spacing on Richmond insert allowables.

SWEC-CAP will provide a program for Richmond insert spacing (see Appendix BB, Section 5.5).

l l

CPPP-7, Revision 3, Section 4.3.1, specifies that rods for use with

)

Richmond inserts are designed to AISC.

Since SWEC has demonstrated j

that the number of equivalent stress cycles on pipe supports at l

CPSES is less than 7,000, then in accordance with AISC 7th Edition, j

(Reference 4.19), Sections 1.7.1 and 1.7.2 and Appendix B, fatigue l

~

is not a concern for threaded rods.

l I

I 0660A-1545405-HC4 A-2

4.0 List of Relevant Documents 4.1 CASE's Proposed Findings of Fact and Conclusions of Law, Sec-tions VII and VIII, dated August 22, 1983 4.2 Affidavit of J.

C.

Finneran, Iotti, and Deubler before ASLB, June 1, 1984 4.3 Reply to NRC Staff questions from W. A. Horin to G. Mizuno dated June 11, 1984 4.4 Reply to NRC Staff questions dated September 1984 4.5 Affidavit of CASE witness M. Walsh before the ASLB, September 11, 1984 4.6 Structural Embedments Specification No. 2323-SS-30, Revision 1, Gibbs & Hill, Inc., February 10, 1984 4.7 Richmond Inserts / Anchorages for Concrete Constructions, Bulletin No. 6, Richmond Screw Anchor Co., 1971 4.8 CPSES Project Technical Office Design Criteria Richmond Insert Bolt Interaction Acceptance Criteria frem E. J. Hee (RLCA) to J. C.

Finneran (TU Electric) dated August 2, 1985 4.9 Testimony of N. H. Williams in response to CASE questions of February 22, 1984, to CYGNA Energy Services, April 12, 1984 4.10 June 20, 1984, and August 9, 1984, meeting with NRC Staff discussing Richmond Inserts' affidavit 4.11 P. G. Hodge, Jr., Interaction Curves for Shear and Bending of Plas-tic Beams, Journal of Applied Mechanics, Vol. 24, 1957,

p. 453 4.12 F. Ellyin and R. Deloin, The Ef fect of Shear on Yielding of Struc-tural Members, Int. Journal of Solids Structures, Vol. 8, 1972,

p. 247 4.13 RLCA Report No. RLCA/P142/01-85/003, Richmond Insert / Structural Tube Steel Connection, Revision 0 dated September 10, 1986 4.14 RLCA Report No. RCLA/P142/01-86/008, Richmond Insert / Structural Tube Steel Connection, Design Interaction Equation for Bolt / Threaded Rod, Revision 0 dated September 10, 1986 4.15 RLCA Report, Richmond Insert / Structural Tube Steel Connection Effect of Thermal Expansion of Tube Steel on Richmond Inserts and Bolts 4.16 SWEC Report No. 15454.05-NZ(C)-002, Interaction Relation for a Structural Membc: of Circular Cross Section, May 1986 4.17 CYGNA Pipe Support Review Issues List, Revision 3, and Transmittal i

Letter No. 84056.106 dated January 9, 1987 0660A-1545405-HC4 A-3

4.18 Applicants' Motion for Summary Disposition Regarding the Effects of Gaps on Structural Behavior Under Seismic Loading Conditions, May 18, 1984 4.19 AISC Specification for the Design, Fabrication, and Erection of Structural Steel for Buildings, 7th Edition, 1969, 5.0 Implementation of the Resolution -5 of CPPP-7, Revision 3, provides the allowable loads for Richmond inserts and threaded rods, along with the proper interaction equations, the modeling procedure for qualifying the Richmond insert when used in conjunction with tube steel for all support configuration types, and the reduced allowables for the insert when spacing and/or concrete edge distance is less than the mininatm required.

It also provides limits on tube steel length on long tube steel members anchored by two or more inserts due to the effects of LOCA-induced thermal expansion.

Proj ect Memorandum No. 141 provides the criteria for the review of Richmond insert to tube steel connection designs to confirm that unequal shear load sharing is not a concern.

0660A-1545405-HC4 A-4

-_-__._-__--a

J.O.No. 15454'05-11H REV.ISION:

1 DATE:

07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX B: LOCAL STRESS - PIPING

]

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f h k' d

D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager -

Production A. W. Chan Assistant Project Manager -

Technical b )() fbtuw R. P. Kl'ause Project Manager

J.O.No. 15454.05-11H APPENDIX B - LOCAL STRESS - PIPING 1.0 Background ~

1.1 CASE contended thac the following issues, related to the inter-actions and local stress due to relative displacements between I

piping and supports, were not properly addressed at CPSES.

1.1.1 Zero Gap Restraints Potential overstress of the frame, welds, or pipe due to radial thermal pipe expansion combined with me-chanical loads.

The most severe case is a hot pipe with cold support at the time of initial startup.

1.1.2 Supports with Integral Attachments Local stresses in the pipe wall induced by integral attachments including

lugs, single and multiple l

trunnions.

Potential overstress of piping, anchor frame, and/or anchor bolts, due to radial thermal pipe expansion combined with mechanical loads for opposing trunnions anchor supports.

1.1.3 Local Stress in Tube Steel Walls 1

Potential overstress of tube steel walls induced by welded attachments.

l 1.1.4 Deflection The inclusion of stiffness from all members of a sup-port assembly in the deflection calculation to meet TU Electric's 1/16-in, deflection limit.

1.2 'TU Electric's position on each of the above items is as follows:

1.2.1 ASME Code Section III has no requirement to evaluate the local stress due to radial thermal expansion.

Analysis of two of the frames indicated that radial thermal expansion of piping is not a problem.

1.2.2 TU Electric performed an analysis of three anchors that indicated all stresses were below allowables.

1.2.3 Local stresses in tube steel walls were assessed by TU Electric on a case-by-case basis when deemed ap-propriate

'sy the engineer.

TU Electric performed several analyses of worst-case supports and showed that all stresses were acceptable.

0660B-1545405-HC4 B-1 l

L___-_______--___

J.O.No.-15454.05-11H 1.2.4 TU Electric's position is that it is the industry practice not to consider local deflection of support members in the overall deflection calculation.

TU Electric performed several worst-case calculations which chowed that even though some deflections ex-ceeded the 1/16-in, limit, the resulting support stiffness was still within the' generic stiffness limitations.

1.3 CYGHA has stated the following:

1.3.1 Reviewed the analyses and accepted allowables used by TU Electric in assessing local stresses.

Based on a finite element analysis it performed, CYGNA agrees with TU Electric's position, although it did not ad-dress the welds.

1.3.2 CYGNA analyzed the local stress in one anchor and indicated no overstressed condition.

1.3.3 Local stresses in tube steel walls are within allow-ables for all supports reviewed by CYGNA.

This can also be determined generically for all those cases where tube wall thickness is equal to or greater than the fillet weld size, since the load path is through the weld.

1.3.4 No apparent assessment or position on this issue.

CYGNA's concerns in Sections 1.3.1 and 1.3.3 are stated in Issue 1 of Reference 4.6.

1.4 The NRC Staff has expressed the following concerns about the items discussed previously:

1.4.1-The NRC Staff concern is that the zero-gap restraints are nonstandard-type restraints and that the forces from radial thermal expansion are not insignificant.

The NRC Staff has expressed doubts as to TU Electric's assumptions regarding temperature distri-bution.

1.4.2 The NRC Staff has not expressed opinions on the re-maining issues.

2.0 SWEC's Understanding of the Issues l

2.1 Zero-Gap Restraints Local stresses induced by radial thermal expansion of piping on the pipe, frame, and welds need to be evaluated.

0660B-1545405-HC4 B-2

J.O.No. 15454.05-11H 2.2 Supports with Integral Attach'ents m

Local stresses in the pipe wall induced by integral attach-ments, including lugs, single and multiple trunnions, need to be addressed.

Radial thermal expansion of pipe needs to be considered in the design of opposing trunnion anchors.

2.3 Local Stress in Tube Steel Wall Local stresses in the walls of tube steel members induced by welded attachments need to be addressed.

2.4 Deflection The flexibility of all member components need to be considered when calculating overall deflection of the support assembly.

3.0 SWEC Action Plan to Resolve the Issues 3.1 Local Pipe Stresses Caused by Bearing Loads 3.1.1 Zero clearance box frames are being eliminated /

modified as discussed in Section 3.2.1 of Appendix D, Pipe Support / System Stability.

3.1.2 Guidelines have been provided in CPPP-7 to assess the circumferential and longitudinal line and point con-tact bearing stresses in piping restrained by support frames.

For the special cases beyond the limits of applica-bility of the CPPP-7 guidelines, finite element ana-lysis is used for evaluation.

3.2 Local Pipe Stress at Integral Attachments SWEC has provided guidelines in CPPP-7 for supports with integral attachments including:

3.2.1 Trunnion-Type Anchor l

Welded on straight pipe (with or without pad)

Welded on elbow

Pipe-through-trunnion and welded on one side

Multiple trunnions at same location

To be evaluated on a case-specific basis 3.2.2 Lug-Type Anchor Welded on straight pipe Welded on elbow 0660B-1545405-HC4 B-3

J.0.No. 15454.05-11H l

3.3 Local Stress in Pipe Support Members The local stress effects of welded attachments on tube steel walls are addressed in Appendix U (Local Stress in Pipe Support l

Members).

l 3.4 Deflection SWEC does not use deflection as a limiting parameter for the piping and pipe support requalification effort.

The i

appropriate parameter is stiffness.

The stiffness of the sup-port assembly is discussed in Appendix E (Pipe Support Generic j

Stiffness).

4.0 List of Relevant Documents 4.1 Affidavit of John C. Finneran, Jr, Regarding Consideration of Loce,1 Displacements and Stresses dated June 18, 1984.

j 4.2 CASE's Answer to Applicants' Statement of Material Facts as to which there is no Genuine Issue Regarding Consideration of Lo-cal Displacements and Stresses dated August 24, 1984.

4.3 Applicant's Reply to CASE's Answer to Applicants' Motion for Summary Disposition Regarding Local Displacements and Stresses dated September 28, 1984.

4.4 Affidavit of John C. Finneran, Jr, in Support of Applicants' Reply to CASE's Answer to Applicants' Motion for Summary Dis-position Regarding Local Displacements and Stresses dated September 28, 1984.

4.5 CASE's Answer to Applicants' Reply to CASE's Answer to Appli-cant's Motion for Summary Disposition Regarding Local Displace-ments and Stresses dated October 4, 1984.

4.6 CYGNA Pipe Support Review Issues List, Revision 3, and Trans-mittal Letter No. 84056.106 dated January 9, 1987.

5.0 Implementation of the Resolution 5.1 Sections 4.4.2 and 4.6, and Attachment 4-6A in CPPP-7, Revi-sion 3, provide guidance for local stress at integral attachments.

5.2 Local bearing stresses in pipe is addressed in CPPP-7, Revi-sion 3, Attachments 4-6B and 4-6C, and Attachment 4-6E issued by PM-139.

l 5.3 Generic stiffness of CPSES pipe supports is addressed in f

Appendix E.

5.4 Local stress on tube steel walls is addressed in Appendix U.

0660B-1545405-HC4 B-4

'J.0'.No. 15454.05-11H REVISION:

1 DATE:

07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX C: WALL-TC-WALL AND FLOOR-TO-CEILING SUPPORTS

/4

[

k[

'D.

C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager -

Production A. W. Chan Assistant Project Manager -

Technical if$t LC R. P. Klause Project Manager i

J.O.No. 15454.05-11H APPENDIX C - WALL-TO-WALL AND FLOOR-TO-CEILING SUPPORTS

1.0 Background

1.1 CASE contended that when a pipe support is attached from floor-to-ceiling or wall-to-wall, the support member is also subject-ed to the building load and acts as a building structural member for which it was not designed, and therefore, may be overstressed.

1.2 The NRC Staff is concerned that small relative building move-ments may yield hi h stresses for these supports.

F TU Electric believed that the NRC Staff concerns of small rela-tive building movements yielding high stresses are based on overly conservative analysis methods.

1.3 TU Electric believed that all large frames (wall-to-wall and floor-to-ceiling supports) were conservatively designed and that a detailed analysis would prove the frames to be adequate as is.

Of 26 supports in CPSES's Unit 1, 7 have slip joints and 4 have small spans and negligible movements and are not considered large-framed supports.

The remaining 15 supports were analyzed for the combined pipe loads and full seismic differential support motion.

TU Electric reported that the resulting stresses in the support were within the Code allow-able values.

1.4 TU Electric also analyzed three supports which span from a wall to a floor or a ceiling. TU Electric reported that the results showed that stresses in pipe support members due to piping loads and differential motion were below allowables.

2.0 SWEC's Understanding of the Issue The effect of differential seismic movement upon supports which span from floor to ceiling, from wall to wall, or from wall to ceiling /

floor should be considered.

The effect of building loads on floor-to-ceiling supports that may act as building columns should be considered.

3.0 SWEC Action Plan to Resolve the Issues 3.1 Floor-to-Floor and Wall-to-Wall Supports (F-F/W-W Supports) 3.1.1 Large Frames Not in the Service Water Tunnel I

i All large frames of this type except those in the service water tunnel are being modified by adding slip joints to alleviate this concern.

I 0660C-1545405-HC4 C-1 i

1 I

i s

.J.O.No. 15454.05-11H 3.1.2 Large Frames in.the Service Water Tunnel The large frames in the service water tunnel are be-ing assessed for the stresses caused by floor live load,. differential-floor / wall. displacements due to long-term concrete creep, thermal expansion, and seismic excitation as specified in Sectio.2 3.3, and defined in Section 3.4.

l 3.1.3 Modifications Supports that are assessed as not being adequate are being modified.

3.2 Wall-to-Floor Supports (Corner Support)

A - generic study' of these supports is being performed utilizing the assessment criteria of Section 3.3.

The calculations of-all corner supports will be marked Confirmation Required in the requalification program.

- Upon completion of the study,- these supports will be reviewed via comparison to the study results, and their designs will be verified or modified as required.

1 3.3 Criteria - Additional Assessment of F-F/W-W Supports In addition to meeting the requirements specified in Table 4.7 2-1 of CPPP-7, the effects of differential floor / wall dis-placement on these supports shall be assessed by the following criteria.

Bases of these criteria are described. in Sec-tion 3.5.

Notations of these criteria are defined in l

Section 3.4.

3.3.1 Differential Displacement (s) Due to Seismic (ASeismic and Long-Term Concrete Creep (ACreep) a.

Support Member and Weld Stresses Load Combination (i) DL + THER + SRSS (0 BET, OCCU) + F

+

3 O

b Creep LL I

(ii) Full range of [SRSS (0 BET, OCCU) + F

]+

3 * ""'

THER range l

'l 0660C-1545405-HC4 C-2 i...i.

.r

....W

J.O.No. 15454.05-11H Allowables:

j Load Combination (i)

Normal stress -

Three -times Level A limit, but less than the smaller of 2 Sy and Su.

Shear stress 1.5 times the Level A limit.

I Weld stress 1.5 times the Level A limit.

NOTE:

The stability of pipe support members shall be considered in the support evaluation by-ensuring. that two-thirds of the critical buckling stress is not exceeded.

Load Combination (ii)

'The stress range shall meet the following allowable stresses:

Normal stress -

Less than 2 Sy or Su.

Shear stress 3 times the Level A limit.

Weld stress-3 times the Level A limit.

b.

Drilled-In Concrete Anchor Bolts and Richmond Inserts Load Combination:

DL +

THER + SRSS (0 BET, OCCU) + F

+F

+F 3

3 at Allowables:

Use Allowables for:

(i) Drilled-in concrete anchor bolts, which are specified in Attachment 4-4 of CPPP-7 (ii) Richmond inserts, which are specified in At-tachment 4-5 of CPPP-7 3.4 Definition of Terms DL

=

Dead load.

A primary sustained load OBET

=

Operating basis earthquake total, i.e.,

the ab-solute sum of the amplitudes of OBE inertia load (OBEI) and load due to OBE anchor movements (OBEA). A primary occasional load.

I 0660C-1545405-HC4 C-3

I' J.O.No. 15454.05-11H OCC (U, E,F)

Primary occasional loads associated with upset,

=

emergency, and faulted operating conditions, respectively SSET

=

Safe shutdown earthquake total, i.e.,

the abso-lute sum of the amplitudes of SSE inertia load (SSEI) and load due to SSE anchor movements (SSEA). A primary occasional load.

Thermal load due to the thermal expansion of the TIER

=

pipe; a primary sustained load.

When all ther-mais have the same sign, consider an additional thermal case of TIER = 0.

SRSS

=

Square root sum of t,he squares.

Occasional loads that are noneyclic must be combined by algebraic sum.

F

=

Support load due to the long-term creep 3

displacement of the floor due to CREEP sustained load F

=

Support load due to the relative motion 3

between the floors and/or walls due to OBE OBE Support load' due to the relative motion F

=

3

8 "" ! # "" 18 ""

SSE l

SSE F

=

Support load due to thermal expansion l

A f the support structure restrained l

THERMAL by the floor slabs F

=

F for corner supports, F 3

3 3

l SEISMIC OBE SSE l

plus F for F-F/W-W sup-3 ports Support load due to the immediate i

F

=

3 deflection of the floor due to g

live load j

l 3.5 Bases of Design Criteria l

3.5.1 Differential Displacement (s) Due to Seismic (ASdh) and Long-Term Concrete Creep (A

)

g 3.5.1.1 Support Member and Weld Stresses 3.5.1.1.1 Load Combination l

NF 3231.1(a) (design, normal, and upset conditions) of ASME Code, 1974 Edition, permits the increase of allowable stress to three times the Level A service 0660C-1545405-HC4 C-4

- - _- __ _____.15454,05-11H' J,0.No.

i limit for the combined mechanical load and the ef-fects which result from constraint of free-end dis-placements in the upset. condition.

Regulatory position C.4 of Reference 4.5 clarifies that this

)

increase is a limit for stress range and should be j

limited to the smaller of 2 Sy and Su to ensure shakedown.

NF 3231.1(b) and (c) specify that constraint of free-end displacement need not be considered in the emer-gency and faulted conditions.

This code position is

. based on the premise that pipe supports, due to their i

basic geometry, contain a certain degree of secondary flexibility.

This flexibiity accommodates the rela-tive movement or thermal expansion between anchorage points in the emergency and faulted conditions which are the results of events with an extremely low prob-ability of occurrence while maintaining the function-al integtity of the support.

These code provisions acknowledge that the geometry l

of the pipe support structure adequately provides for the expansion or contraction appropriate to the func-tion of the support as required by XVII-2271.3.

The above discussion can' be similarly supported by a review of the ASME 1983 NF Section 3121.11, 3322.7(3), and Table NF-3623(b)-1, Notes 4 and 6.

Corner Supports For corner supports, which is a typical design com-monly used in the industry, A shall be due to Se ic OBE.

SecondarystressesneednoksEeaddressedinthe emergency and faulted conditions in accordance with NF 3231.1(b) and (c).

F-F/W-W Supports Due to the unusual geometry of floor-to-floor and wall-to-wall supports, displacements due to both thermal expansion and SSE may not be adequately pro-vided for and must be assessed. Therefore, for F-F/

W-W supports, A shall include a due to SSE and Seis i thermal expansion of Ebe support structure.

3.5.1.1.2 Load Combination Allowables Allowable Stresses for Load Combination (i) (see Section 3.3.1)

This combination considers the amplitude from zero value to the maximum combined mechanical and dynamic loads.

The resulting normal ' tresses are limited to s

0660C-1545405-HC4 C-5 m..._..~_

._______a

-J.0.No. 15454.05-11H-

)

1 the lesser of the value that ensures shakedown (three times Level A or 2Sy) and the ultimate strength of the material (Su).

However, the shear stress shall be conservatively further limited to 1.5 times the Level A allowable to prevent shear yield.

Allowable Stresses for Load Combination (ii)

(see Section 3.3.1)

The normal stress range is limited to the value that ensures shakedown to elastic behavior (2Sy, but con-servatively is not to exceed the ultimate strength (Su)).

The shear stress range shall be limited to twice the maximum for load combination (i).

3.5.1.2 Drilled-In Concrete Anchors and Richmond Inserts Since concrete anchor and Richmond inserts are struc-tural elements not within the jurisdictional boundary of subsection NF, the provision of 3.4.1(a) does not apply.

Allowables in Attachments 4.4 and 4.5 of CPPP-7 will be applied.

4.0 List of Relevant' Documents 4.1 CASE's Partial Answer to Applicants' Statement of Haterial Facts, in the Form of Affidavit of CASE Witness, Mark Walsh, August 27, 1984 4.2 Affidavit of R. C. Iotti and J. C. Finneran, Jr.,

Regarding Differential Displacement of Large Frame Pipe

Supports, June 22, 1984 4.3 Applicants' Reply to CASE's Answer to Applicants' Motion for Summary Disposition Regarding Differential Displacement of Large-Framed, Wall-to-Wall and Floor-to-Ceiling Pipe Supports,

October 1, 1984 4.4 CASE's Proposed Findings of Fact and Conclusions of Law (Walsh/

Doyle Allegations),Section VI, dated August 22, 1983 4.5 Service Limits and Loading Combinations regarding Class 1 Lin-ear Type Component

Supports, USNRC staff Regulatory Guide 1.124, Revision 1, January 1978 4.6 Table S, Tensile and Yield Strength for Weld-Me+ al, SFA-5.5, Part C,, ASME B&PV Code,Section II, 1983 Edition 5.0 Implementation of the Resolution The procedure as discussed in Section 3.0 is incorporated into CPPP-7, Revision 3, -19.

The administrative procedure for the qualification of wall-to-wal? and corner supports is incor-porated in PM-039.

0660C-1545405-HC4 C-6 1

.J.O.No.,1545405.05-11H-REVISION:

1 DAT'E: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX D:

PIPE SUPPORT / SYSTEM STABILITY

/Y & $

/

D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1

. Engineering Mechanics Division f.4.re m.

r C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. V. Chan Assistant Project Manager -

Technical ffb? t'L cr R. P. Klause Project Manager l

l l

1 1

}

C____._____._______...___._.

J.O.No. 1545405.05-11H i

APPENDIX D - PIPE SUPPORT / SYSTEM STABILITY

1.0 Background

CASE in Reference 4.6 and CYGNA in Issue 6 of Reference 4.7 identi-fied pipe support configurations installed at CPSES that are potent-ially unstable.

CYGNA further stated that the column-strut stab-ility assessment may not reflect the composite buckling capacity of each member.

1.1 NRC Staff Definition of Stability Stable means that a support cannot shift or move to an unquali-fled position.

Unqualified position means a position other than the position assumed in the piping stress analysis.

1.2 Configurations That Are Potentially Unstable The following are configurations which are potentially unstable because they have the potential to move axially along the pipe and/or rotate around the pipe creating a three pin linkage system.

1.2.1 Zero-Clearance Box Frames Supported by Single and/or Multiple Struts 1_.

___I g -- -

--l x

x m'

;.T. : :

($b :<

1 b.)

6.___rwl'J: l

)

L._ _.." ' -- I l l l

I _...

...I

-rl p

p c-e

.n

( a% ).

7

'3 h-Case 1 Case 2 Case 3

1 l

0660D-1545405-HC4 D-1

J.O.No. 1545405.05-11H 1.2.2 Uncinched U-Bolts on Single Strut or Snubber Y

h Buu.s n c " - l===:n::r-7,

=

C 4f 1.2.3 Multi-Strutted Frame Gang Supports j

i l...

-- l i i

.". i <

, i +.

l l

,I I

klI i

3-g s

v l! I.h! h,fiI

-m

-^^

0660D-1545405-HC4 D-2

J.O.No. 1545405.05-11H In addition to stability, the NRC Staff noted that multistrutted frame which supports multiple piping systems should be evaluated for the dynamic interac-tions of the frame and the multiple piping systems.

1.2.4 Trapeze Supports With U-Bolts Yrn

[~~

~5 4

In addition to stability, the NRC Staff noted the following concerns:

1)

Out-of plane twisting motion when struts are in compression.

2)

U-bolts are not designed for twisting - see ge-neric issue on U-bolt twisting (Appendix X).

3)

Unequal load distribution in the struts.

1.3 Column-Strut' Stability E, f, Et I, P

m j

(2)

(1) 12 Lt Firure 1 j

Pr.a/t) s Tirure 2 - Me=ber 2 Buckled l

0660D-1545405-HC4 D-3

l J.O.No. 1545405.05-11H CYGNA is also concerned that the stability (allowable axial load) of the strut-column assembly may not reflect the compos-ite buckling capacity of each member.

1.4 overall System Stability The NRC Staff stated that experienced piping engineers should ensure system stability by reviewing the piping and support configurations.

2.0 SWEC's Understanding of the Issues 2.1 Definition of Stability 1

Stability of supports must be assured to meet the following definition:

Stable means that a support cannot shift or move to an unqualified position.

Unqualified position means a posi-tion that exceeds the specified tolerances from the posi-tion assumed in the piping stress analysis.

2.2 The following support configurations are potentially unstable because they may move axially along the pipe and/or rotate about the pipe creating a three-pin linkage system:

1)

Zero-clearance box frames supported by single or multiple struts 2)

Uncinched U-bolts on a single strut or snubber 3)

Multi-strutted

frames, both single support and gang support 4)

Trapeze supports with U-bolts (concern of NRC Staff) 2.3 The stability assessment of column-strut structures must re-flect the unique load pattern on the column.

2.4 Overall System Stability The overall piping system stability must be ensured.

3.0 SWEC Action Plan to Resolve the Issues 3.1 Definition of stability - implement definition of stability as stated in Section 2.1.

3.2 Modify potential unstable configurations as follows:

)

0660D-1545405-HC4 D-4 i

J. O. No '. 1545405.05-11H' 1

3.2.1 Zero-Clearance Box Frame Supported by Single or Multiple Struts Mod 1 -

Remove the existing box frame, and replace it with a standard pipe clamp- (adjustment of the existing strut may be required).

Mod 2 -

Replace the support with a rigid frame.

3.2.2 Uncinched U-Bolts on Single Strut or Snubber All supports of this nature are being eliminated or modified by replacing the U-bolt assembly with a design consistent with the required support function.

3.2.3 Multi-Strutted Gang Support Frames Redesign these supports as rigid frames.

3.2.4 Trapeze Supports With U-Bolts' All supports of this nature are being modified as described in Appendix L,

Axial, Rotational, and Trapeze-Type Restraints.

l 3.3 Column-Strut Stability The equations to evaluate the critical buckling load of a column-supported strut is addressed in Section 4.2.4 and -9 of CPPP-7.

3.4 Review of Overall Piping System Stability The overall piping system will be stable provided the following two conditions are met:

1.

Each installed support is individually qualifled to be stable (in accordance with the definition in Section 2.1) 2.

The system integrity is analyzed for deadweight, thermal, and applicable occasional loads (fluid transients) and seismic excitations in three orthogonal directions are within the code allowables.

4.0 ListofRelevanh. Documents 4

4.1 Affidavit of John C. Finneran, Jr, Regarding Stability of Pipe Supports and Piping Systems, June 17, 1984

]

4.2 CASE's Motions and Answer to TU Electric's Motions for Summary Disposition Regarding Stability of Pipe

Supports, October 15, 1984 0660D-1545405-HC4 D-5 yiii-i mulmmmm nu

-ad-m r

L

]

'J.O.No. 15454'05.05-11HL 4.3 Testimony of N. H. Williams in Response to CASE Questiori of February 22, 1984, to'CYGNA Energy Services 4.4 Letter to Mr. J. B. George of TU Electric from N. H. Williams of CYGNA. in reference to stability of pipe

supports, February 19, 1985 4.5 Letter to Mr. J. B. George of TU Electric from N. H. Williams of CYGNA in reference to stability of pipe

supports, April 30,'1985 4.6 CASE's Proposed Findings 'of Fact and Conclusions of Law,Section III, dated August 22, 1983 4.7 CYGNA Pipe Support Review Issues List, Revision 3, and Trans-mittal Letter No. 84056.106' dated January 9, 1987.

~

5.0 Implementation of the Resolution The procedure for. modifying potentially unstable support configura-tions and-for. the evaluation of the strut-column stability is in-cluded in CPPP-7, Revision 3 in Section 4.2.4 and Attachment 4-9.

I 4

I 0660D-1545405-HC4 D-6 e

E

J.O.No. 15454.05-11H REVISION:

1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT i

APPENDIX E: PIPE SUPPORT GENERIC STIFFNESS k

M[

D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production

~

A. Y. Chan 1.

Assistant _ Project Manager -

Technical b{

d4L LL. --

R. P. Klause Project Manager i

J.0.Ho. 15454.05-11H APPENDIX E - PIPE SUPPORT GENERIC STIFFNESS

1.0 Background

An assumed set of generic stiffness values was used to represent the pipe supports in te pipe stress analysis for Classes 2 and 3 piping at CPSES. The supports were designed to allowable stresses and to a deflection limit of 1/16 in. for Level B (upset condition) loads. No check was performed on the support stiffness, since it was as-sumed that the 1/16-in. deflection limit would ensure that actual stiffness was reasonably close to the assumed generic values.

However, supports that were lightly loaded and designed to a 1/16 in. deflection limit may have stiffnesses that are much lower than the assumed generic values.

An evaluation by TU Electric of the stiffnesses of supports in piping systems demonstrated that the variation in stiffnesses was as much as three orders of magnitude in some situations. The concern of the NRC Staff, CYGNA as stated in Issue 13 of Refer-ence 4.9, and CASE is that since support stiffness was not checked in the design process, then there is no assurance that the assumed set of generic stiffness values adequately represents the stiff-nesses of the installed supports. Therefore, the results of the pipe stress analysis may not be valid. CASE also contended that flexibilities of all pipe support compo-nents should be included in the support assembly stiffness calcula-tion, such as U-bolts and base plates and the potential effect of oversized bolt holes. 2.0 SWEC's Understanding of the Issues l 2.1 Assurance should be provided that assumed generic stiffness values adequately represent the stiffness values of installed supports. 2.2 For a support consisting of several components, the stiffness of each component should be included in the stiffness evaluation. ) 2.3 The effect of oversized bolt holes in a base plate on the stiffness of a support needs to be considered. j 3.0 SWEC Action Plan to Resolve the Issues. 3.1 Generic Stiffness The SWEC generic stiffness methodology is discussed in Reference 4.8. l Generic stiffness values that are representative of the sup-ports installed in the plant were developed. In addition, the 066'0E-1545405-HC4 E-1

J.O.No. 15454.05-11H minimum stiffness that can be appropriately represented by the generic value was established. The following outlines the action plan: 3.1.1 Determination of Generic Values The following three types of supports were selected from the CPSES pipe supports installed in the plant: 1) Rigid supports, including frames and struts 2) Anchors 3) Snubbers For rigid supports, generic values were developed for groups of pipe sizes. For snubbers, generic values were based on snubber sizes. The generic values for anchors were developed in terms of nondimensional values, which are independent of pipe sizes. The nondimensional stiffness values of all sample anchors for all pipe sizes can thus be used together in developing histograms. 3.1.2 Pipe Support Stiffness Histograms For all the supports evaluated, stiffness values were calculated. Histograms of the calculated stiffnesses were devel-oped and representative values (median values) determined. 3.1.3 Minimum Acceptable Stiffness for Use of the General l Value The piping responses calculated based on generic stiffness values may not be valid if the pipe support stiffnesses are significantly lower than the generic value. To ensure that the use of generic values will produce valid pipe stress analyses, a minimum stiff-ness value has been established. This minimum stiffness was determined with consider-ation of its effect on thermal, static, and dynamic responses. The approach used simplified piping mod-1 els and fundamental engineering principles. t 0660E-1545405-HC4 E-2 1

J.O.No. 15454.05-11H 3.1.4 Screening Procedure Before the beginning of pipe stress analysis, each pipe support is assessed to determine whether its stiffness falls above the minimum stiffness; if so, it is assigned the generic stiffness. The stiff-nesses of commonly rised supports is provided to facilitate the assessment. When a pipe support's stiffness has been determined to fall below the minimum value, the calculated stiffness value is used in the pipe stress analysis in lieu of the generic value. 3.2 Support Stiffness Evaluation The stiffness of each component in a support assembly, such as the stiffness of the vendor-supplied components, structural l

members, or base plates is assessed in the calculation of the j

support stiffness. i 3.3 Effect of Oversize Bolt Holes on Support Stiffness Appendix M, Bolt Hole Gap, concluded that the CPSES anchor-bolt hole sizes are in compliance with ASME 1985 Summer Addenda NF-4721(a) and are not oversized. Therefore, the in-stalled anchor bolt hole sizes at CPSES are in accordance with the code for bearing connections and, consistent with industry practice, is not included in the support stiffness essessment. 4.0 List of Relevant Documents 4.1 Pipe Support Generic Stiffness Study, CPPA-48,974, TU Electric, February 13, 1986 4.2 TU Electric Pipe Support Design Guideline Section XVIII, Addi-tional Guidelines for the Design of Safety Class Pipe Supports, March 22, 1985 I 4.3 Affidavit of R. C. Iotti and J. Finneran, Jr., Regarding Use of Generic S,tiffnesses Instead of Actual Stiffnesses in Piping Analysis, May 21, 1984 4.4 Affidavit of CASE Witnesses J. Doyle and M. Walsh, CASE's Par-tial Answer to Applicants' Statement of Material Facts as to which there is no Genuine Issue Regarding Applicants' Use of I Generic Stiffnesses Instead of Actual Stiffnesses in Piping Analysis, August 24, 1984, and August 27, 1984 i 4.5 CYGNA Phase 3 Final

Report, TR-84042-01, Revision 1, Appendix J, Note 8 dated November 20, 1984 i

0660E-1545405-HC4 E-3

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N. H. Villiams' (CYGNA) letter to V. Noonan (USNRC), ~0 hen Items

. Associated with Walsh/Doyle Allegations,- 84042.022^ dated January. 18, 1985 '4 ' ',4. 7 Testimony of N. H. Willias:s in response to CANE questions'of February 22, 1984,. to CYGNA Energy Servicca 7 .4 4.8' St%C Report No. 15454.05.N(C)-003, Generic, Tipo Support Stiff-ness Values for Piping Aralysis dated Septembite 1986 [.( 4.9 ;CYGNA. Pipe Support Review Issues List Eevision 3, CYGNA Letter ,h i4o). 84056.106 dated January 9, 1987 5.0)ImplementationoftheResolution sh i 4 set.ofCPSE'S generic; stidfness values and acceptable minimum val-aes have been incorporated in.tne design criteria, CPPP-7, kdvision 3, Section 3.10.8,4 including the guidance presented for pipe support stiffne s representation in Section 3.10.8.2. / l The 'stiffnesses of commonly use.d ' supports have been provided in graphic and tabular forms and. incorporated in Attachment 4-18 of '7g. CPPP-7 to facilitate the:pssessrient of support stiffnesses, as spec- - j ified by Section 4.3.1.2 of CPPP-7,. Revision 3. g c 'g 3 / "/ ? . a,. Ur i .I ,e I y V5 -9 1 ,, Y h 1 1 0660E-1545405-HC4 E-4

J

J.O.No. 1545405.05-11H REVISION:

1 DATE: 07/24/87 j j 'TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STO'..'E & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE ETRESS AND PIPE SUPPORT l GENERIC ISSUES REPORT APPENDIX F: UNCINCHED U-BOLT ACTING AS A TWO-WAY RESTRAINT D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 1 Engineering Mechanics Division g f' C. A. Fonseca Project Engineer - Unit 2 Assistant. Project Manager - Production W A. W. Chan Assistant Project Manager - Technical f %K' R. P. R14use Project Manager 9

l J.O.No. 15454.05-11H i i I APPENDIX F - UNCINCHED U-BOLT ACTING A'S A TWO-WAY RESTRAINT i

1.0 Background

l CASE contended that uncinched U-bolts attached to rigid frames that are analyzed as one-way (vertical) restraints will behave as two-way restraints (vertical and lateral). Consequently, CASE stated the following: 1.1 Failure to include both the lateral and vertical restraining i action of the U-bolts (two-way restraint) invalidates the re-sults of pipe stress analyses that modeled the U-bolts as one-way restraints. 1.2 U-bolts used for one-way (vertical) restraints on rigid frames w131 not meet the manufacturer's recommended interaction limits when the lateral loads from thermal and seismic movement are applied. 2.0 SWEC's Understanding of the Issues 2.1 Uncinched U-bolt supports attached to rigid frames that are analyzed as vertical restraints will offer some lateral resis-tance to pipes. 2.2 Uncinched U-bolts on rigid frames must be assessed for the in-teraction of lateral, normal, and axial (friction) loads. 3.0 SWEC Action Plan to Resolve the Issue 3.1 For pipe sizes equal to or greater than 8 in. NPS, replace the uncinched U-bolt with a component that complies with the sup-port function. 3.2 Modeling In the piping analysis, model all uncinched U-bolt supports for pipe sizes 6 in, and smaller that are attached to rigid frames as two-way restraints. 3.3 Development of the Uncinched U-Bolt Qualification Guideline I 3.3.1 STRUDL models of U-bolts were developed to derive the stiffness value and resultant loading (moment, shear, and tension) at the attachment to the frame. A fric-tion coefficient of 0.3 was considered acting in the axial direction of the pipe, for static (signed) loads only. Friction was ignored for dunamic (cy-clic) loads. 3.3.2 The interaction formula developed for circular cross sections was used to determine allowable U-bolt ratings. 0660F-1545405-HC4 F-1

J.O.No. 15454.05-11H i 1 3.3.3 The uncinched U-bolt qualificat. ion procedure is in-corporated in Section 4.2.5.2 and Attachment 4-3 of CPPP-7.- 3.3.4 Stiffness values for uncinched U-bolts, modeled as two-way restraints were developed and issued in l CPPP-7, Revision 3, Attachment 4-18. 2 4.0 List of Relevant Documents 4.1 Affidavit of R. C. Iotti and J. C. Finneran, Jr., Regarding U-bolts used as one-way Restraints Acting as two-way Re-straints, May 23, 1984 4.2 CASE's Answer to Applicants' Motion for Summary Disposition of CASE's Allegations Regarding U-bolts Acting as two-way Re-straints, August 20, 1984. 4.3 CASE's Proposed Findings of Fact and Conclusions of Law, Sec-tion II, dated August 22, 1983 5.0 Implementation of the Resolution 5.1 Section 4.2.5.2 and Attachment 4-3 of CPPP-7, Revision 3, pro-vide piping analysis guidance for the proper modeling and anal-ysis of uncinched U-bolts as two-way restraints. 5.2 Section 4.3.2.2 and Attachment 4-18 of CPPP-7, Revision 3, pro-vide stiffness values of U-bolr.s. 1 i l I i 0660F-1545405-HC4 F-2 t k _o

LJ.O.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECEIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX G: FRICTION / / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production 4-A. W. Chan Assistant Project Manager.- Technical [ a c <-. - R. P. Kfa'use Project Manager i i

J.O.No. 15454.05-11H APPENDIX G - FRICTION

1.0 Background

The CPSES pipe support designs by ITT-Grinnell and TU Electric Pipe Support Engineering (PSE) do not consider friction loads when the predicted pipe movement is less than 1/16 in. CASE stated that this practice is unacceptable, and that the addi-tion of these loads could result in an overstressed condition for some supports. TU Electric contended that there is safficient conservatism in the existing design such that the increase in support load and resulting member forces and stresses due to friction would not be significant. CASE and TU Electric agreed that the support friction load for pipe movements less than 1/16 in, would be the lesser of the normal load multiplied by the coefficient of friction and the force required to deflect the support a distance equal to the piping thermal movement. The.}UTC Staff does not believe that TU Electric has provided suffi-cient technical justification for the practice of ignoring friction for small pipe movements at CPSES. CYGNA performed an independent review of this issue and concluded that ignoring friction for movement less than 1/16 in is acceptable based on industry practice, a TU Electric sample reanalysis, the factors of safety available for normal designs, and the 1974 ASME I Code as the code of record. However, in Issue 29 of Reference 4.6, CYGNA reopened this issue based on code changes reflected in ASME III, 1983, NF 3121.2 and requested further response from TU Elect.ic. 2.0 SWEC's Understanding of ti.p Issues Friction needs to be evaiuated for static and/or steady-state pipe movement in the unrestrained direction, even if the movement is less than 1/16 in. 3.0 SWEC Action Plan to Resolva the Issue Although SWEC also believes that friction loads for movements less than 1/16 in. are insignificant, the CPSES requalification design criteria includes a requirement that friction loads be considered for sigaed loads (i.e., static and/or steady state loads) regardles's of pipe movements. 4.0 List of Relevant Documents 4.1 Applicants' Reply to CASE's Answer to Applicants' Motion for Summary Disposition Regarding Consideration of Friction Forces, September 14, 1984. 0660G-1545405-HC4 G-1

l J.O.No. 15454.05-11H ) i + 4.2 CASE's Answer to Applicants' Reply to CASE's Answer to Appli-cants' Motion for Summary Disposition Regarding Consideration of Friction Forces, October 1, 1984. 1 4.3 Affidavit of John C. Finneran, Jr., Regarding Consideration of f Friction Forces in the Design of Pipe Supports with Small Ther-I mal Movements, May 16, 1984. 4.4 CASE's Answer to Applicants' Motion for Summary Disposition Regarding Consideration of Friction Forces in the Design of Pipe Supports with Small Thermal Movements, August 6, 1984. 4.5 CASE's Proposed Findings of Fact and Conclusions of Law (Walsh/Doyle Allegations), August 22, 1983. 4.6 CYGNA Pipe Support Review Issues List, Revision 3, and Trans-mittal Letter No. 8/056.106 dated January 9, 1987 5.0 Implementation of the Resolution Section 4.7.3 and Attachment 4-7 of CPPP-7 require that friction be considered in all load cases for signed loads (i.e., static and/or steady state loads) regardless of pipe movement. l l 0660G-1545405-HC4 G-2 l 1

'J. 0 '. No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX H: AWS VERSUS ASME CODE PROVISIONS f f/Wh~ /WM D. C. Foster R, R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer. Unit 2 Assistant Project Manager - Production [ 4 __ - A. K Chan ~ Assistant Project Manager - Technical / /' e 6 n R. P. Klause I Project Manager .f l i

l J.O.No. 15454.05-11H ] l APPENDIX H - AWS VERSUS ASME CODE PROVISIONS

1.0 Background

i CASE contended that differences exist between certain weld design j requirements in the AWS and ASME codes. The differences involve two issues: welds in skewed T-joints and local stresses at connections between tube steel structural members. 1.1 CASE Concerns CASE identified four weld design rules specified by the AWS Code but not specifically addressed in the ASME Code as follows: 1.1.1 Effective throat for skewed T-joint welds - CASE con-tended that TU Electric incorrectly accounted for the effective throat of skewed fillet welds. 1.1.2 Skewed T-joint angularity limits - CASE contended that AWS specifies angular limits on skewed T-joints while ASME does not. 1.1.3 Local stresses at structural tubing connections -CASE contended that AWS contains design methods for ad-dressing local stresses in structural tubing connec-tions while ASME does not. 1.1.4 Structural tubing connections with Beta equal to 1.0 - CASE contended that AWS contains a design meth-od for addressing web crippling in matched tube steel connections while ASME does not. 1.2 TU Electric's Response TU Electric's response to-each of the concerns follows: 1.2.1 The 1974 Edition of the ASME Code contained no ex-plicit requirements for the effective throat of skewed fillet welds. The TU Electric design is gov-erned by a through thickness check, which more than offset the need for an effective throat reduction. In addition, a review of 201 support calculations demonstrated that these designs were adequate when considering effective throat reduction. 1.2.2 CPSES weld procedures are qualified by test, which overrides the AWS angle limitations. 1.2.3 Local stresses are addressed on a case-by-case basis. TU Electric reviewed 171 supports.with D/2t ratio >10 on Unit I to address the local stress issue. One support was modified as a. result of local overstress. s 0660H-1545405-HC4 H-1

J.O.No. 15454.05-11H' 1.2.4 'Y does contain guidance for web crippling, and TU Electric followed that guidance. 1.3 NRC Staff's Position As a result of TU Electric's - response,.the NRC Staff estab-lished the following positions: 1.3.1 TU Electric should provide further evidence that.they comply with the updated ASME requirement on the ef-fective throats of fillet welds in skewed T-joints. 1.3.2 The AWS Code does not deviate from the ASME Code. Both the AWS and ASME Codes do not set forth angular-ity limits when the weld procedures are qualified by test. 1.3.3 1N Electric should show that the six supports listed by CASE are included in their 171 sample with D/2t > 10. 1.3.4 TU Electric should provide further evidence that web crippling is checked. 2.0 SWEC's Understanding cf the Issues 2.1 Skewed T-Joint Welds (Sections 1.1.1 and 1.1.2) 2.1.1 The effective throat of skewed T-joint welds must be properly evaluated in the pipe support design. 2.1.2 CPSES uses qualified welds which obviate the angular-ity restriction in either AWS or ASME. 2.2 Local Stresses at Tube Steel Structural Connections I (Sections 1.1.3 and 1.1.4) Local stress of tube steel structural connections and web crip-pling of tube steel structural connections are addressed in Appendix U. 3.0 SWEC Action Plan 3.1 Skewed T-Joint Weld 3.1.1 Guidelines for the evaluation of the effective throat of-skewed T-joint

welds, using guidance from AWS D1.1(85) Figure 10.13.13B and Table 10.13.3, were incorporated in CPPP-7, Revision 3, -2.

I 3.1.2 No action required. 1 e 0660H-1545405-HC4 H-2

J. O. No,' 15454.05-11H 4.0 List of Relevant Documents 4.1 NRC Staff Response to Applicant's Motion for Summary Disposi-tion on AWS and ASME Code Provisions on Weld Design dated November 2, 1984. 4.2 Affidavit of David Terao on AWS and ASME Code Provisions on Weld Design dated November 2, 1984. 4.3 CASE's Answer to Applicant's Statement of Material Facts as to which there is no Genuine Issue Regarding Certain Case Allega-tions Regarding AWS and ASME Code Provisions Related to Design Issues dated August 4, 1984. 4.4 Affidavit of J. C. Finneran, R. C. Iotti, and J. D. Stevenson Regarding Allegation Involving AWS Versus ASME Code Provisions Attachments 1 and 2 dated May 15, 1984. 4.5 CASE's Proposed Findings of Fact and Conclusions of Law (Walsh/ Doyle allegations), Section V, August 22, 1983. 5.0 Implementation of the Resolution Section 4.4 and Attachment 4-2 of CPPP-7, Revision 3, pcovide guid-ance for the design evaluation of skewed joint welds. l i 1 0660H-1545405-HC4 11 - 3 __________--__O

J.O.No. 15454.05-11H. REVISION: I DATE: 07/24/87 -TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX I: A500, GRADE B TUBE STEEL $Y l D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division /r_'? sea. / C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production D A. W. Chan Assistant Project Manager - Technical I f MW R. P. Klah'se Project Manager l

.J.O.No. 15454.05-11H l APPENDIX I - A500, GRADE B TUBE STEEL

1.0 Background

The design of CPSES pipe supports uses'a design yield strength _Sy of 42 kai for A500, Grade B, tube steel. (cold formed) in accordance with ASME Code Case N71-9. A later version, ASME. Code Case N71-10, revised the yield strength from 42 ksi to 36 ksi. CASE contended that all designs for tube steel supports at CPSES should be revised to incorporate the lower design yield strength. 2.0 SWEC's Understanding of the Issues ASME Code Cases N71-10 through N71-14 specify the design yield strength Sy of A500, Grade B tube ste.el to be 36 ksi. Use of Sy = 42 ksi in CPSES support design must be justified. 3.0 SWEC Action Plan to Resolve the Issues 3.1 Establish Design Guidance 3.1.1 Prior to the issuance of ASME Code Case N71-15, CPSES pipe support desig'n adequacy was confirmed using l Sy = 36 kai. The use of Sy = 42 ksi was allowed on a case-by-base basis, and calculations were marked CON-FIRMATION REQUIRED. 3.1.2 Code Case N71-15 was issued on December 16, 1986, specifying the yield strength for A500, Grade B tube 4 l steel as 46 ksi. Pending the NRC approval of this ~ Code Case, SWEC will determine the appropriate impact on the design criteria. However, consistent with commitments made to CASE (Reference 4.7), should the NRC allow the increase to 46 ksi, SWEC will not increase the design yield strength beyond 42 ksi. 4.0 List of Relevant Documents 4.1 Applicants' Reply to CASE's Answer to Applicants' Response to Board's Partial Initial Decision Regarding A500 Steel Dated November 16, 1984 4.2 Affidavit of J. C. Finneran, Jr., Rcgarding CASE's /.nswer Con-cerning A500 Steel, November 16, 1984 4.3 Affidavit of W. P. Chen on Revised A500 Steel Yield Values Dat-ed May 29, 1984 4.4 Applicants' Response to Partial Initial Decision Regarding A500 ~ Steel Dated April 11, 1984 4.5 Affidavit of J. C. Finneran, Jr., Regarding A500 Tube Steel Dated April 10, 1984 06601-1545405-HC4 I-1

1 =.7,0. No. 15454.05-11H -4.6 -Testimony of N. H. Williams in Response to CASE Questions of February 22, 1984, to CYONA Energy Services 4.7 Meeting Between CASE and TU Electric with SWEC in Attendance, Large Bore Pipe Supports, March 12, 13, and 14, 1987 5.0 Implementation'of the Resolution CPPP-7, Section 4.7.2.1, specifies that the design of pipe supports using A500, Grade B tube steel for CPSES shall be verified for a yield strength of 36 ksi. However, designs that fail at Sy = 36 ksi but pass for Sy = 42 kai will not be modified and will have their calculations marked CONFIRMATION REQUIRED. Pending NRC approval of Code Case N71-15, SWEC will determine the appropriate impact on these support designs; however, independent of the NRC Staff response, SWEC will not increase the yield strength beyond 42 ksi. I l l 1 t l l 1 l 1 j 1 i 0660I-1545405-HJ4 I-2

J.O.No.-15454.05-11H-REVISION: 1 .DATE: 07/24/87 ) TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION. STONE &' WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT t APPENDIX J: TUBE STEEL SECTION PROPERTIES k / ( D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division Tw C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A.'WT Chan Assistant Project Manager - Technical A k lls W R. P. Klause Project Manager l l f I

J.O.No. 15454.05-11H. E APPENDIX J - TUBE STEEL SECTION PROPERTIES

1.0 Background

CASE had questions regarding the section properties and flare bevel welds in the design of tube steel members as follows: 1.1 Section Properties The section properties for A500 Grade B cold-formed tube steel used in the pipe support design at CPSES were obtained from three authoritative source documents. Each source document listed slightly different section properties. These three Source Documents are:

1) AISC Manual of Steel Con-struction, 7th Edition; 2) 1974 Welded Structural Tube Insti-tute (WSTI) Manual of Cold-Formed Welded Structural Steel Tubing; and 3) AISC Manual of Steel Construction, 8th Edition.

l . Prior to January 1981, pipe supports were designed by ITT, NPSI, and PSE using section properties from Source Document 1. From January 19P1 through January 1982, pipe supports were de-signed by PSE using section properties from Source Document 2. From January 1982 to ' the present, ITT, NPSI, and PSE obtained section properties from Source Document 3, which lists section properties representative of cold-formed tube steel. The sec-tion properties (moment of inertia) of tube steel listed in Source Document I are based on a corner tangent radius (R ) of l 3t and are slightly smaller than the properties listek in Source Document 3, which are based on a corner tangent radius l of 2t. The section properties of tube steel listed in Source Document 3 are up to 11 percent smaller than those listed in Source Document 2, which are based on a corner radius of it. TU Electric indicated that the moment of inertia is probably the most critical property and attempted to show that the dif-ference in this property is insignificant. CASE disagreed and stated that the most significant property value is dependent on how the member is being used. As an example, a bending member may require a high section modulus and an axially loaded member may need a high cross-sectional area. 1.2 Flare Bevel Weld The 8th Edition of AISC states that the effective throat of flare bevel grove welds is t = 5/16 R unless it can be es-larger effecfive throat can be obtained. The tablished that a design of flare bevel welds at CPSES has been examined by the NRC Staff / SIT and reported that PSE used te = 0.645t. After changing criteria, TU Electric reported to CYGNA that PSE used te = t. 0660J-1545405-HC4 J-1

J.0.No. 15454. 05 -11H CASE contended that flare bevel welds at T-joints cannot be accurately analyzed muless an accurate corner radius is known. 2.0 SWEC's Understanding of the Issues 2.1 Section Properties 2.1.1 The appropriate section properties of the cold-formed tube steel supplied by the vendor to CPSES need to.be eletermined. 2.1.2 The section properties to be used for design assessment of CPSES pipe supports need to be established. 2.1.3 The adequacy of pipe supports designed using section prop- .erties from all three source documents needs to be evaluated. 2.2 Flare Bevel Welds The effective throat of flare bevel welds at CPSES needs to be established. 3.0 SWEC Action Plan to Resolve the Issues 3.1 Section Properties SWEC reviewed the material manufacturer's dimensional standards for A500, Grade B tube steel supplied to TU Electric. SWEC conducted a survey of the ASTM A500 (standard specifica-tion for cold-formed welded and seamless structural tubing in rounde and shapes), which includes a 12 year span starting from issue date 1974 through 1986. The survey indicated that the standard mill tolerances did not change during this period of time. It can be concluded that the fabrication tolerances and section properties of tube steel members in CPSES have been maintained to a consistent standard. SWEC also confirmed that Welded Steel Tube Institute (WSTI) amended its 1974 issue (1st Edition) to agree with the 8th Edi-tion of the AISC. This amendment is the latest revision to date. These section properties are based on a corner tangent radius.of 2t and are c'onsidered representative of cold-formed tube steel. SWEC resolutions are summarized as follows: The use of section properties in AISC Manual of Steel Con-struction, 8th Edition, is appropriate, since it repre-sents the actual cold-fo rmed tube steel used at CPSES. The 8th Edition of AISC is used by SWEC in the selection of section properties for structural tube steel. 0660J-1545405-HC4 J-2

J.O.No. 15454.05-11H SWEC surveyed tube steel corner dimensions on installed supports at CPSES (Reference 4.5) and confirmed that the installed supports have a nominal 2T corner radius. 3.2 Effective Throat for Flare Bevel Weld SWEC performed a survey of tube steel dimensions on installed ASME III NF pipe supports at CPSES and weld tests of worst-case configurations to determine the appropriate throat to be used in flare bevel welds (Reference 4.5). Based on the results of this survey it was concluded that an effective throat of L =t - 1/16 in, is justified for all tube cizes except TS 2*x 2. For TS 2 x 2 sections an effective throat t =t-1/8 in. is appropriate. Existing welds on TS 2 x 2 sections will be requalified to meet the t = t-1/8 in, criteria, unless it can be verified that i the w61d has a larger effective throat by performing a field l inspection of the weld in accordance with the methods described i in PM-140. l l l Specification No. 2323-MS-100 has been revised by DCA No. 41100 (issued March 2,1987) to ensure that an effective throat of a0y new wor /16 in. t =t-1 is achieved for welds on all tube sizes for k in the future. 4.0 List of Relevant Documents 4.1 Affidavit of J. C. Finneran and R. C. Iotti Regarding CASE's Allegation Involving Section Property Values, Attachment I Dat-ed May 18, 1984 4.2 CASE's Answer to Applicants' Statements of Material Facts as to Which There Is No Genuine Issue Regarding CASE's Allegations Regarding Section Property Values, Dated August 12, 1984 4.3 Affidavit of J. C. Finneran, Jr., Regarding Information Related to Section Property Values Dated November 9, 1984 4.4 CASE's Proposed Findings of Fact and Conclusions of Law, Section XVIII, dated August 22, 1983 i 4.5 SWEC Report 15454-N(C)-004, Survey of Structural Tube Steel Dimensions to Verify the Effective Throat of Flare Bevel Welds dated March 23, 1987 i 5.0 Implementation of the Resolution j 5.1 Section 4.3.2.1 of CPPP-7 specifies that structural tube steel section properties should be selected from the 8th Edition of the AISC steel manual in the CPSES pipe supports requalifica-tion. l 0660J-1545405-HC4 J-3 i i

J.O.No. 15454.05-11H 5.2 Section 4.4 and Attachment 4-2 of CPPP-7, Revision 3, as amend-ed by PM-140, specify the effective throat of flare bevel welds. l l I l 0660J-1545405-HC4 J-4

J.O.No. 15454.05-11H Revision: 1 Date: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX K: U-BOLT CINCHING /Y / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division-C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - l Production A. W. Chan Assistant Project Manager - Technical k$ tex V R. P. Klau'ss Project Manager I

J.O.No. 15454.05-11H APPENDIX K - U-BOLT CINCHING

1.0 Background

The design of a single-strut / single-snubber cinched U-bolt support in CPSES received attention from CASE, NRC Staff, ASLB, and CYGNA. The concerns are the support's potential instability, material prohibition / caution by the AISC and ASME Codes, and induced local stresses in the pipe and,U-bolt due to the cinching process. An uncinched U-bolt does not provide resistance to rotation about the axis of the run pipe. As discussed in Appendix D, an uncinched U-bolt and cross piece (tube steel or plate) support, with a single strut / snubber, will result in ' a classical unstable three pin situa-tion when a compressive load acts on the strut / snubber. To elimi-mte the instability of this type of support, CPSES cinched the U-bolt.to increase the friction force between the pipe and the as-sembly, in effect making it behave as a clamp. Although cinching down the U-bolt will correct the stability problem, it raises the iu. lowing areas of concern: Stresses induced in the run pipe, U-bolt, and cross piece due to freload, pipe thermal and pressbre expansion, and external loading. The loss of U-bolt preload due to mechanical and. material relaxation. The proper estimate of preload due to galling under the U-bolt nut. CASE observed that the cinched U-bolt relies on friction to provide stability and the AISC Code prohibits the use of A-307 material in friction connections. Since SA-36 and SA-307 mate-rials are similar, CASE contends that SA-36 material is prohib-ited from use in friction connections. The AISC and ASME Codes do not recommend the use of A-307 mate-rial when subject to a high number'of loading cycles. Since SA-36 and SA-307 materials are similar, the NRC Staff was con-cerned with the fatigue life of SA-36 material used as cinched U-bolts. TU Electric addressed the first two concerns through a series of tests and finite element analyses (References 4.6, 4.7, 4.8, and 4.11). A simplified closed form design procedure was developed based on the test and analysis program. TU Electric stated that existing single strut / snubber cinched U-bolts comply with this de-sign procedure. TU Electric also stated that the AISC Code prohibition against SA-307 material in friction connections and the caution about the i l l 0660K-1545405-HC4 K-1 {

J.O.No. 15454.05-11H use of SA-307 ' material in connections subject to cyclic load does not apply to SA-36 material used in cinched U-bolts at CPSES. 2.0. SWEC's Understanding of the Issues The major concerns regarding the practice of cinching U-bolts have been categorized into the following eight areas: 2.1 Stability of the installed single-strut / single-snubber cinched ~ U-bolt restraint design must be confirmed. (Reference 4.1) 2.2 The forces and stresses that are induced in the cinched U-bolt must be considered. (Reference 4.3) 2.3 The local stresses induced in the pipe by the cinched U-bolt must be considered. (Reference 4.13) 2.4 The local stresses in the crosspiece due to the U-bolt nut and possible galling of the tube wall must be considered. 2.5 The thermal transient load between the pipe and the cinched U-bolt must be considered. The worst condition could occur when the pipe is heated up suddenly while the U-bolt is at am-bient temperature. (Reference 4.12) 2.6 SA-307 material was not used in cinched U-bolt designs. l 2.7 AISC Code 7th Edition Table 1.5.2.1 prohibits the use of SA-307 j as bolting material in friction connections. SA-36 and SA-307 materials are similar. ASME III Code Inquiry NI86-030 (Ref-erence 4.14) clarifies that cinched U-bolts are not friction connections. Ilowever, since the U-bolt design relies on fric-tion to provide stability, the bases of the AISC prohibition need to be understood and addressed. 2.8 SA-36 material used in cinched U-bolt designs is subject to load cycling, which must be considered in the qualification. ASME III Appendix XVII, Table XVII-3230-1, Footnote 4 and AISC i 7th Edition, Appendix B, Table B2,. Footnote 4 state "where stress reversal is involved, use of A307 bolts is not recom-mended." Material fatigue is the primary concern. 3.0 SWEC Action Plan to Resolve the Issues Due to the extensive engineering effort required to qualify cinched U-bolt type supports with struts and snubbers, and the anticipated problems in maintaining required preload levels, all cinched U-bolt / crosspiece supports with struts and snubbers will be modified to other support designs consistent with the required support functions. l j 0660K-1545405-HC4 K-2

J.0.No. 15454.05-11H 4.0 List of Relevant Documents 4.1 ASLB Memorandum and Order at 27, 28, 33-41, December 28, 1983, and reconsidered in ' Memorandum and Order at 20, February 8, 1984 4.2 ASLB Memorandum and Order at 28 and 33, December 28, 1983, and reconsidered in Memorandum and Order at 22-40, February 8,1984 4.3 ' ASLB Memorandum and Order at 33-41, December 28, 1983, and re-considered in Memoratidum and Order at 24-5 February 8,1984 4.4 CASE's Proposed Finding of Fact and Conclusions of Law, Section IV, August 22, 1983 4.5 TU Electric's Motion for Summary Disposition of CASE's Allega-tions Regarding Cinching Down of U-bolts, June 29, 1984 4.6 Affidavit of R. C. Iotti and J. C. Finneran, Jr., Regarding Cinched-Down U-bolts, June 22, 1984 4.7 Westinghouse Report No. WCAP-10620, U-bolt Support / Pipe Test, July 1984 4.8 Westinghouse Report No. WCAP-10627, 'U-bolt Support Assembly Finite Element Analysis, July 26, 1984 4.9 TU Electric's Response to NRC Staff Questions of Meeting of August 8, 9, and August 23, 1984 4.10 CASE Answer to Applicants' Statement of' Material Facts as to Which There is No Genuine Issue Regarding to Consideration of Cinched U-bolts, Affidavit of CASE Witness J. Doyle, October 8, 1984 4.11 Verification of Cinched U-bolts with Single Strut / Snubber Robert L. Cloud Associates, July 11, 1985 4.12 CYGNA Phase 3 Open Item Report, March 25, 19,85 j 4.13 ASLB Memorandum and Order at 33-41, December 28, 1983, and re-considered in Memorandum and Order at 25-6, February 8, 1984 4.14 ASME III Code Inquiry NI86-030, Section III, Division 1, NF-3324.6(a)(3)(b)- Friction Type Joints, NF-3324.6(a)(4) Slip Resistance Friction Type Joints, NF-3225.4, Friction Type

Joints, 1983 Edition - with the Winter 1985 Addenda, dated June 25, 1986 5.0 Implementation of the Resolution In accordance with CPPP-7, Revision 3, Section 4.2.5.1, cinched U-bolts with struts and snubbers are not being used at CPSES.

Existing strut / 0660K-1545405-HC4 K-3 i

J.O.No. 15454.05-11H snubber supports with cinched U-bolts are being modified as required to remove the cinched U-bolts. i 1 ) l 1 i I l l l' { 1 l 0660K-1545405-HC4 K-4 i l I )

J.O.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION ' STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX L: AXIAL, ROTATIONAL, AND TRAPEZE RESTRAINTS / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division 1_w C. A..Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. W. Chan Assistant Project Manager - I Technical kl [.btil&d' \\ R. P. Klauss' Project Manager l l $)

J.O.No. 15454.05-11H APPENDIX L - AXIAL, ROTATIONAL, AND TRAPEZE RESTRAINTS -] l 1

1.0 Background

1.1 Axial Restraints With Trunnions CASE maintains' that the modeling of axial supports with double trunnions as only axial restraints ignores the rotational resistance imposed on the run pipe. The rotational restraint will affect the predicted stress levels in the piping and the support loads. 1.2 Axial Restraints With Lugs Distributing Load to Frames and Pipe Clamps i CASE contends _ that lug-type supports should be assessed assuming only one lug taking the load for the following reasons: Construction tolerances allow for the possibility of initial contact with the frame of only a single lug. Thus the frame should be de-signed, assuming loading to the frame, through the single lug locat-ed at the extreme point of the structure from the frame reaction points. With perfect installation for all lugs along a circumferential plane, angularity of the pipe through rotation of the pipe at the support node point will result initially in only a single lug coming into contact with the mating structure. Thus, the frame should be designed assuming single point' loading as stated above. 1.3 Distribution of Load to Component Legs of Trapeze-Type Supports CASE contends that component parts fo rming legs of a trapeze-type support should be sized for more than 50 percent of the total load to account for differences in structure stiffness at the attachment points'of the trapeze legs. CASE further contends that for trapeze-type supports involving snub-bers, it is not practical to assume that two such devices will lock up at precisely the same acceleration level in a sesimic event. 2.0 SWEC's Understanding of the Issues 2.1 The rotational resistance induced by eccentric trunnion supports should be incorporated into the pipe stress analysis. 2.2 Axial frame supports utilizing lugs must be assessed for the proper distribution of load between the lugs and frame. 2.3 For trapeze-type supports, the load in each leg should be designed to account for the effects of differences in stiffness of structural attachment points and differential snubber lockup. 0660L-1545405-HC4 L-1

i J.0.No. 15454.05-11H 2.4 The potential twisting of trapeze supports with snubbers and struts may be assessed in the designs. 3.0 SWEC Action Plan to Resolve the Issues 3.1 Axial Restraints 3.1.1 Lugs Engaging Rigid Frames These support types are modeled in the pipe stress analysis as transla-tional restraints at the pipe centerline. i 3.1.1.1 Two Lugs on Each Side of Frame 1. The lug adequacy and local stress check are based on the total l load applied through a single lug. 2. The frame is then evaluated assuming a single point loading of the total load. The load is applied to the frame at the loca-tion of the lug that produces the most critical stress condi-tions in the frame. 3.1.1.2 Four or More Lugs on Each Side of Frame 1. Gaps between the frame and the lug are closely controlled in accordance with Attachment 4-11 of CPPP-7. Therefore, it is unreasonable to assume all the load on one lug. Even if the pipe rotates, a second lug will come in contact. Therefore, the lug adequacy and local stress check are based on one-half -of the total load applied through each lug. 2. The frame is then evaluated assuming loading at two points of one-half of the total load each. The load is applied to the frame at the location of the two lugs that produces the most critical stress conditions in the frame. 3.1.2 Trapeze-Type Supports With Riser Clamps and Lugs During system review, required by CPPP-6 and CPPP-9, a determination is made to model these support types as either transnational, restraints (both struts / snubbers act) or an eccentric tran'slational ' restraint with one strut / snubber (an of f-axis restraint). This determination is based on the relative stiffness of the support structures. If the stiffness of each structure determined.'n accordance with Attach-ment 4-18 of CPPP-7 is greater than K. in accordance with CPPP-7 Section 3.10.8, then the support is modele M s a transnational restraint. If both stiffnesses are not greater than K. but are similar (the stiffness of the stiffer support is not greate*r"l.han B times the stiff-f ness of the other), then the support is also modeled as a transnational f restraint. B is a function of pipe size and riser clamp C-C dimension and represents the physical limits when the riser clamp. rotates on the top lug pair and begins to jack against the bot' tom lug pair on the 1 0660L-1545405-HC4 L-2 a

J.O.No. 15454'.05-11H 3 opposite side of the pipe centerline. For stiffness ratio's greater than B, the load on one strut approaches the total load and the support acts as an eccentric transnational restraint. ) If the stiffnesses are not similar and both are not greater than K I then the support is modeled as an eccentric transnational restraint OkEh-one strut / snubber removed, i.e., the support contains a riser clamp or off-axis clamp and one strut / snubber. 1 The qualification engineer must initiate a modification request to have the strut or snubber of the softer support removed. 3.1.2.1 Supports Modeled as Transnational Restraints These supports are modeled in the pipe stress analysis as axial re-straints at the pipe centerline. 1. The riser clamp is qualified in accordance with the NPSI Certi-fied Design Report Summaries (CDRSs), or Grinnell Design Report Summaries (DRSs). For NPSI riser clamps, in the event of un-even load distribution, the higher of the two loads is compared to one-half the CDRS value. Grinnell DRS values were derived based on the entire load applied to one a rm of the clamp. i I 2. If the component standard supports are spring hangers, each spring is evaluated for the statically distributed pipe load. Each lug' is qualified for the total load distributed to -'r the lugs. (No more than two lugs are considered.) 3. If the component standard supports are struts or snubbers, each component is qualified for 75 percent of the total design load. Each lug is qualified for half of the total load. 3.1.2.2 Supports Modeled as an Eccentric Restraint The support is modeled as an eccentric support in the stress analysis in accordance with Section 3.10.6.2 of CPPP-7. 1. The riser clamp is qualified for the total support load applied to one arm in accordance with the NPSI Certified Design Report Summaries (CDRSs), or Grinnell Design Report Summaries. 2. The strut / snubber is designed for the total load from the stress analysis. 3, Each lug is qualified for the load F, (as shown on page L-4). 4 0660L-1545405-HC4 L-3

J.0.No. 15454.05-11H F Q r Eg bE r ,,o f f j e D -On _7 Q i--H ' 8 LU IU Use with off-axis clamp and strut or snubber Q w 2> t i a (0.707e + 0.25) F =F D s 3.1.3 Trape,se Supncets with U-Bolts These supports are eliminated (if acceptable to Pipe Stress) during sys-tem review. Supports that cannot be eliminated during system review are modified as follows: 3.1.3.1 U-Bolt Trapeze with Snubbers 1. Change the snubber to a rigid (if acceptable to Pipe Stress) and follow the rules for a U-bolt trapeze with struts. (3.1.3.2) 2. Replace the support with a single snubber and standard clamp in the same vicinity. This may require that the support be skewed, relocated, and/or the supporting structures redesigned. 3.1.3.2 U-Bolt Trapeze with Struts 3.1.3.2.1 Modeling Requirements These supports are modeled in' the pipe stress analysis as transnational restraints at the run pipe centerline. 1. The support stiffness is calculated at the pipe centerline as discussed in Attachment 4-18 of CPPP-7. 2. The support mass is luraped at the pipe centerline as discussed in Attachment 3-4 of CPPP-7. 0660L-1545405-HC4 ' L-4

J.O.No. 15454.05-11H 3. Each strut and its support structure is qualified to the load resulting from the static distribution of the total pipe load. 3.1.3.2.2 Redesign Options 1. Replace the support with a single strut and clamp. This may require that ", support be relocated, skewed, and/or the sup-porting stru cure redesigned. 2. Redesign the support as a frame serving the same support function. 3. Replace the U-bolt with a special strap (see paragraph 3.1.4) and one of the following: a. Add a pair of stabilizing struts parallel to the pipe centerline normal to the crosspiece from the crosspiece to a supporting structure. (See Section 3.1.4.4, Item 5.) b. Add two clamp anchors to restrain the axial load and twisting moment. (See Section 3.1.4.4, Item 6.) c. Add three pairs of lugs as described in paragraph 2.1.4. (See Section 3.1.4.4, Item 4.) 3.1.4 Design of Strut Trapeze Supports with Straps Trapeze supports with struts are redesigned to address three concerns. 1. Axial stability of the support - The crosspiece is prevented from moving axially along the pipe (X axis). 2. Rotation of the crosspiece with respect to the pipe around a line (V axis) normal to the pipe centerline and normal to the crosspiece is prevented. 3. The modification does not provide a torsional restraint to the pipe (i.e., prevent rotation about the X axis). Options 3a, 3b, and 3c of paragraph 3.1.3.2.2 address these three con-cerns. First, the use of the straps releases the torsional restraint. The parallel stabilizing struts restrain the crosspiece from axial and rotational movement. Both the lugs and the clamp anchors restrain the crosspiece from axial and rotational movement with respect to the, pipe. 0660L-1545405-HC4 L-5

J.0.No. 15454.05-11H 3.1.4.4 Typical Modified Trapeze V V d 1 4 6 n 1 \\ l C +X H= l l w l g-______ ..o = _ _\\ MN 1 MN d 5 1 3 \\ I l I 2 h h ' )' ( ) ( Notes Coordinate 8" stem 1. Strap V = normal to the pipe 2. Strut and crosspiece 3. Trapeze Crossmember 4.* Lug (if chosen) H = normal to the pipe 5.* Stabilizing Strut (two required) and parallel to the (if chosen) crosspiece 6 '.

Clamp Anchor (if chosen)

X = axial to the pipe

Note:

Items 4, 5 and 6 are not used together. Only one is to be used for any one support. 'l t' Ot,60L-1545405-HC4 L-6

.{ '

J.O.No. 15454.05-11H 3.2 Rotational Restraints 3.2.1 Trapeze-Type Supports with Trunnions 1. Pipe stress analysis includes in the modeling of piping system eccentricities representing the offset of.the standard suppo'rt components. Accordingly, individual node point loads are pro-vided for each side of the trapeze, except springs, which e.re modeled at the pipe centerline. 2. If component standard supports are spring hangers, each spring is designed for the statically distributed pipe Toad. 3. If component standard supports are struts, the design load for each strut is the loading from the support summary for that side of the trapeze. 4. If component standard supports are snubbers, the design load for each snubber is derived by taking loading for each leg and increasing it by 20 percent to account for possible differen-tial snubber lockup., Each snubber is then qualified for the increased load on its leg as discussed above. 5. Trunnion size is selected and local stress check performed based on the design loadings used for the selection of compo-nent parts for each side of the trapeze. 3.2.2 Single-Sided, Eccentric Loading Supports 3.2.2 1 Single-Sided, Eccentrically Loaded Supports With Trunnions, Axial and Lateral Restraint Applications The pipe stress analysis includes in the modeling of the piping system the integrally attached trunnions. Accordingly, a node point is provided representing the attachment point of the component standard to the trun-nion with loading information available for that point. Trunnion, compo-nent part(s), and supporting structure are qualified based on this loading information. 4.0 List of Relevant Documents, 4.1 Affidavit of ' R. C fotti and J. C. Finneran, Jr., Regarding Consideration of Force Distribution in Axial Restraints, dated July 9, 1984 4.2 Affidavit of Case Witness Mark Walsh - CASE's Partial Answer to Applicants' Statement of Material Facts as to which there is no Genuine Issue Regarding Allegations Concerning Consideration of Force Distribution in Axial Restraints, dated August 27, 1984 4.3 CASE's Proposed Findings of Fact and Conclusions of Law, Section XII, dated August 22, 1983 0660L-1545405-HC4 L-7

J.0.No. 15454.05-11H 1 l l 5.0 Implementation of the' Resolution 1 L Sections 3.10.6.2 and 4.2 and Attach- 'l L 5.1 CPPP-7, Revision 3, ment 4-8 establish the procedure for the qualification of axial and rotational restraints. 5.2 CPPP-7, Revision 3, Section 4.6 establishes the analysis proce-dure for integral attachments. 0660L-1545405-HC4 L-8 m

J.O.No. 15454'.05-11H Resision~1 Date: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION 4 -STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX M: BOLT HOLE GAP ( D. C. Foster R. R. Wrucke . Chief Engineer Project Engineer - Unit 1 Engineering Mechanies DivAsion C. A. Fonseca Project Engineer - Unit " Assistant Project Manager - Production D A.'W. Chan Assistant Project Manager - Technical p f A LL W R. P. Kla'tise Project Manager ] s, b

.J.0.No.'15'54.05-11H 4 APPENDIX M - BOLT HOLE GAP 1.0. Background Bolt hole gap as used herein refers to the radial clearance between an anchor bolt and the bolt hole edge in pipe support member / base plate. 1.1 CASE maintains that bearing-type connections are inappropriate for supporting structures during seismic events. The bases for this concern are as follows: 1.1.1 It is impossible to predict how many bolts are in-volved in the transfer of shear. Inelastic action that distributes the shear load to all anchor bolts is appropriate for static loads only. 1.1.2 Bolt holes in support base plates are oversized. Bearing connection is not allowed if the bolt hole is greater than a standard size hole in accordance with the AISC Code. 1.1.3 Presence of gap in joints under dynamic conditione adversely affects a _ system's seismic response. The usual procedure is to assume that two bolts react to the load regardless of the number of bolts in the pattern. 1.2 TU El tetric 1.2.1 TU Electric recognized that different radial gaps may exist between the anchor bolts and bolt holes in a base plate. The shear load across the connec; ions may be shared initially by one or two bolts, until inelastic action distributes the shear equally to all bolts. This ' reliance on inelastic action is well recognized as being a valid assumption in elastic design. 1.2.2 The gaps between the bolts and the bearing surface in .CPSES are -sufficiently small such that the bolt de-flection will not cause failure. TU Electric's affi-davit (R'eference 4.1) presented two sets of data of bolt capacities in shear. The lowest factor of safe-ty was 4.56 for Hilti bolts and 3.2 for Richmond inserts. 1.2.3 The effect of gaps is beneficial to reduce pipe stresses and support loads due to increased damping on earthquake excitation. 0 0660M-1545405-HC4 M-1 e ___________________m__ _U

i .J.O.No. 15454.05-11H 1.3 NRC Staff The NRC Staff agreed that it is an industry practice to assume that all bolts will react equally to a shear load. l 1.4 CYGNA CYGNA studied the effects of the bolt holes 1/8 in. bigger than the anchor bolts of 1-in, diameter and found that this hole size only reduced the factor of safety from 5.0 to 4.8. The study was based on a bearing-type connection which can reach its design ultimate capacity, even though all bolts were not stressed tc the same level (Reference 4.4). 2.0 GWEC's Understanding of the Issues Bolt hole sizes for bearing connections in base plates and tube steel must comply with the requirements of ASME NF-4721, 3.0 SWEC Action Plan to Resolve the Issues 3.1 ASME Code Table NF-4721(a)-1 specifies the allowable bolt hole sizes for bearing-type connections as follows: Bolt Size Hole Size Equal to or less than 1 in. Bolt diameter +1/16 in. I 1/8 in. to 2 in. Bolt diameter +1/8 in. The allowable bolt hole sizes of the installed CPSES base plates are as follows: Bolt Size Hole Size Equal to or less than 3/4 in. Bolt diameter +1/16 in. 1 in. to 1 1/2 in. Bolt diameter +1/8 in. Therefore, it can be seen that only the bolt holes for 1-in. diameter bolts at CPSES have an allowable size larger than the code allowable by 1/16 in. The 1985 Summer addenda of the ASME Section III Code, paragraph NF-4721(a) permits the increase of this hole size by 1/16 in. As clarified by 1985 Summer Addenda NF-4721(a), the anchor bolt hole sizes at CPSES are not oversized. Therefore, these con-nections are designed / evaluated as bearing connections with shear load shared equally by all bolts. t ASME III, 1985 Summer Addenda NF-4721(a) has been added to the CPSES Code of Record in CPPP-7, Revision 3, Section 2.2, and Specification No. MS-46A. 3.2 SWEC review has concluded that the Richmond insert to tube steel connection configuration may not have been considered in 0660M-154540S-HC4 M-2

J.O.No. 15454.05-11H 'the above code paragraphs. Therefore, Richmond insert to tube steel connection designs will be reviewed to confirm that un-equal shear load sharing is not a concern. 4.0 List of Relevant Documents Affidavit of R. C.'Iotti and J. C. Finneran, Jr., Regarding the 4.1 . Effects of Gaps on Structural Behavior Under Seismic Loading Conditions, May 18, 1984 4.2 CASE's Answer to the Applicants' Statement of Material Facts in the Form of Affidavit of CASE Witness M. Walch, August 12, 1984 4.3 Affidavit of R. C. Iotti and J. C. Finneran, Jr., in Reply to CASE's Answer to the. Applicants' Motion for Summary Disposition Regarding the Effects of Gaps, October 26, 1984 4.4 CYGNA's response to CASE Question No. Doyle 16 4.5 D. D. Vasarhelyi' and W. N. Chang, Misalignment in Bolted Joints, Journal of the Structural Division, ASCE, Vol 91, ST 4, August 1965 4.6 J. W. Ficher and J. H. A. Struik, Guide to Design Criteria for Bolted and Riveted Joints, Wiley, New York,1974, pp 190 - 193 4.7 E. G.

Burdette, T.

C. Perry, and R. R. Runk, Load Relaxation. Tests of Anchor in Concrete, presented at ACI Annual Conven-tion, Atlanta, Georgia, January 1982 4.8 CASE's 4th Round Ans'wer to Applicants' Reply to CASE's Answer to Applicants' Motion for Summary Disposition Regarding the Effects of Gaps, December 19, 1984 5.0 Implementation of the Resolution ASME III, 1985 Summer Addenda NF-4721(a) has been added to the CPSES Code of Record in CPPP-7, Revision 3, Section 2.2, and Specification No. MS-46A.. Proj ect Memorandum No. 141 provides the criteria for the review of Richmond insert to' tube steel connection designs to confirm that unequal shear load sharing is not a concern. i 0660M-l545405-HC4' M-3 i J

J.0.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 i TU ELECTRIC COMANCHE. PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX N: OBE/SSE DAMPING / Y' l / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division gf - _ _,m C. A. Fonseca l Project Engineer - Unit 2 Assistant Project Manager - Production M-A. K Chan Assistant Project Manager - l Technical i: c_c - R. P. Klause Project Manager i

J.O.No. 15454.05-11H ) APPENDIX N - OBE/SSE DAMPING

1.0 Background

The NRC Staff's SIT, CASE, and CYGNA stated that higher damping val-ues than the allowables in Regulatory Guide 1.61 (RG 1.61) were used in the stress analysis at CPSES. 1.1 NRC Staff / SIT Concern SIT contended that the damping values used in Pipe Stress Problem 1-041 were different from the regulatory positions in RG 1.61. 1.2 CASE Concern CASE stated that piping systems containing active valves should use the lower damping for active components, in accordance with footnote 2 to Table 1 of RG 1.61. 1.3 CYGNA Concern CYGNA in Issue 15 of Reference 4.5 reported that in certain stress problems, which are comprised of piping of atfferent sizes, the damping values for the 12 in. or greater piping were used even though the problem contained piping smaller than 12 in. 2.0 SWEC's Understanding of the Issues 2.1 Proper damping should be used in the analysis of piping systems that contain active valves. 2.2 Proper damping should be used in the analysis of mixed-size piping systems. 3.0 SWEC Action Plan to Resolve the Issues 3.1 Regulatory Guide 1.61 Daoping 3.1.1 CPPP-7, Revision 3 specifies the use of Regulatory Guide 1.61 damping for piping systems. The lower damping for active components in Regulatory Guide 1.61 is not applicable to the piping analysis, since piping systems are not active components. 3.1.2 CPPP-7, Revision 3 also specifies that mixed-size piping systems (containing pipes above and below 12-in. NPS) will be conservatively evaluated with the lower damping values of RG 1.61. .0660N-1545405-HC4 N-1

J.O.No. 15454.05-11H 3.2 Code Case N-411 Damping Use of the damping values specified in Code Case N-411 that are applicable to all pipe sizes has been approvea for implementa-tion at CPSES by the NRC Staff. CPPP-7, Revision 3, authorizes the use of Code Case N-411 for all systems, including mixed-size CPSES piping systems, except where stress analysis is per-formed using the Independent Support Motion Method. 4.0 List of Relevant Documents 4.1 Applicants' Motion for Summary Disposition Regarding Alleged Errors Made in Determining Damping Factors for OBE and SSE Con-ditions, May 16, 1984 4.2 CASE's Answer to Applicants' Motion for Summary Disposition Regarding Alleged Errors Made in Determining Damping Factors for OBE and SSE Loading Conditions, August 6, 1984 l 4.3 Applicants' Reply to CASE's Answer to Applicants' Motion Re-I garding Alleged Errors Made in Determining Damping Factors for OBE and SSE Loading Conditions, September 21, 1984 4.4 CASE's Answer to Applicants' Reply to CASE's Answer to Appli-cants' Motion Regarding Alleged Errors Made in Determining j Damping Factors for OBE and SSE Loading Conditions, l I October 2, 1984 4.5 CYGNA Pipe Stress Review Issues List, Revision 3, anc Transmd.t-tal Letter No. 84056.106 dated January 9, 1987 5.0 Implementation of the Resolution l 5.1 Regulatory Guide 1.61 and Code Case N411 damping values are specified in CPPP-7, Revision 3, Section 3.4.5.4.1. 1 5.2 The proper use of damping values is a review item in the pipe l stress analysis checklist of CPPP-6 and 9. .'i 1 l t i I I 0660N-1545405-HC4 N-2

'J.O.'No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC ' COMANCHE PEAK STEAM ELECTRIC STATION UNIT 1. STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT I. GENERIC ISSUES REPORT APPENDIX 0: SUPPORT MASS IfY / d D. C. Foster R.-R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. W. Chan Assistant Project Manager - i Technical Y,o.; /$bMCLL R. P. Klaisse Project Manager i i

J.O.No. 15454.05-11H APPENDIX 0 - SUPPORT MASS

1.0 Background

The support mass contribution to.the piping model was not always considered in the CPSES pipe stress analysis, because it was consid-ered small relative to the total mass of the piping system. CASE contended that the weight contribution of the support to the piping system is significant and it cannot be omitted from the analysis. 2.0 SWEC's Understanding of the Issue Pipe support mass should be considered in the pipe stress analysis. 3.0 SWEC Action Plan to Rescive the Issue Support mass, eccentric and noneccentric, is considered in the anal-ysis of all CPSES piping systems. 4.0 List of Relevant Documents 4.1 CASE's Proposed Findings of Fact and Conclusions of Law, Section XIV, dated August 22, 1983. 5.0 Implementation of the Resolution 5.1 The support mass is accounted for in pipe stress analyses in accordance with CPPP-7, Section 3.10.4. A detailed procedure j for pipe support mass determination and inclusion in the piping 1 system analysis is included in Attachment 3-4 of CPPP-7, with additional guidance on the modeling of eccentric mass included in Attachment 3-11. q 5.2 A review item on support mass ic included in the pipe stress analysis checklist af CPPP-5 and CPPP-9. 1 06600-1545405-11C4 0-1

J.O.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX P: ITERATIVE DESIGN 9 / h Y D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project M nager - Production i A.' K Chan Assistant Project Manager - Technical l_ f CM - R. P. Klause Project Manager 1 9

J.O.No. 15454.05-11H APPENDIX P - ITERATIVE DESIGN

1.0 Background

CASE's concern is that the CPSES piping analysis and pipe support design responsibilities were fragmented, and that too much responsi-bility was delegated to the pipe support vendors and field forces, which may cause inadequacy. TU Electric responded to the above concern as follows: The CPSES design was developed by the process that Gibbs,& Hill first laid out the piping, by means of a thermal expansion stress analysis of practical pipe routing. The piping arrangement was then sent to the pipe support ven-dor, who located pipe supports and determined the support type (spring, rigid, constant support, snubber, etc) in accordance with criteria set forth by Gibbs & Hill and in areas that were judged free from interference. These pipe support locations and types were then used by Gibbs & Hill to perform a complete (thermal, deadweight, and seismic) analysis. If the results were satisfactory, the support loads were then transmitted to the pipe support vendor to design the pipe supports. Support deaigns were then issued for construction. It was ac-knowledged that even with careful initial design, there is a possibility that the pipe support cannot be constructed as de-signed. In the cases of unconstructable designs, CMCs were prepared and sent to the vendor for review. If it was neces-sary to change the location or type of a support, the proposed design was sent to Gibbs & Hill's Site Stress Analysis Group l (SSAG), who decided whether it was necessary to modify the stress analysis. Once a satisfactory solution (support configurations) for all the supports on a given piping system had been determined, the final design was sent to Gibbs & Hill (either New York or SSAG) for final review and as-built stress analysis. If the pipe stresses were satisfactory, the results of the analysis were sent to the pipe sup" rt vendor for final certification that l the support designs were adequate. In canclusion, it can be seen that Gibbs & Hill, the party re-sponsible for the piping system design, was involved in the pipe and support design continually from the beginning to the end. 2.0 SWEC's Understanding of the Issues The piping design organization must be involved continuously during the iterative design process (pipe stress analysis / pipe support 0660P-1545405-HC4 P-1

J.O.No.'15454.05-11H design / construction /as-built verification) to reach a satisfactory design.' 1 3.0 SWEC Actior. Plan to Resolve the Issues This issue of fragmented responsibility between piping analysis and I support design is resolved by the integrated design process in the SWEC requalification program. All ASME Class 2 and 3 piping systems and supports are being requalified by SWEC in accordance with CPPP-7 which provides consistent criteria for both pipe stress analysis and pipe support design. Each pipe stress problem is reviewed in accor-dance with Section 7.3 of CPPP-6. or CPPP-9, respectively, as a sys-tem by a pipe stress engineer and a, pipe support engineer to ensure that the interactions between the pipe and the pipe supports are i properly accounted for in the requalification effort. 1 The ASME Class 1 piping system are analyzed by Westinghouse, while the supports are qualified by SWEC in accordance with CPPP-7. The interface and control of data transmittal between Westinghouse and SWEC are controlled by CPPP-6 and 9. 4.0 List of Relevant Documents 4.1 TES Draft Letter No. 6216-7 dated February 21, 1985, from D. F. Landers to V. S. Noonan, Director Comanche Peak Project,

USNRC, which transmitted Technical Report No. TR-6216B, Preliminary Consulting Report on Comanche Peak Steam Electric Station - Piping and Support Design 4.2 CASES's Proposed Findings of Fact and Conclusions of Law, Section XXIV, August 22, 1983 5.0 Implementation of the Resolution Controlled copies of CPPP-6, CPPP-7, and CPPP-9 are issued to the pipe stress and pipe support supervisory personnel assigned to the SWEC CPSES effort.

A consistent set of criteria thus is being used j by all SWEC personnel in the requalification program for CPSES. SWEC has an integrated design process and interfaces between all disciplines are controlled. Personnel performing. the requalifica-tion effort are trained by project management in the uses of the applicable project procedures. Compliance to the project procedures is ensured by the SWEC Corpo-rate Quality ' Assurance Program. Adequate implementation of resolu-tions for all the generic technical issues is a subtask within SWEC's management plan for project quality in CPPP-1. i 0660P-1545405-HC4 P-2 .I

'J.O.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE:& WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE. SUPPORT GENERIC ISSUES REPORT APPENDIX Q: MASS POINT SPACING l ~ D. C. F.oster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division f'Tesa. C. A. Fonseca Project Engineer - Unit 2 Assistant Project M nager - Production .A. W."Chan Assistant Project Manager - Technical llSttkL - R. P. Klause Project Manager i 1 l

J.0.No. 15454.05-11H APPENDIX Q - MASS POINT SPACING i

1.0 Background

j I CYGNA, in Pipe Support Issue 5 and Pipe Stress Issue 1 of Refer-ence 4.2, stated that the mass point spacing for the dynamic analy-sis did not always meet the project criteria. 2.0 SWEC's Understanding of the Issues Some analyses of CPSES piping did not include mass points between supports in the same direction or between anchors and adjacent sup-ports. Adequate mass point spacing of piping model for CPSES requalification program must be ensured. 3.0 SWEC Action Plan to Resolve the Issues SWEC guideline for locating lumped mass points in a piping system is specified in CPPP-7. 4.0 List of Relevant Documents 4.1 CYGNA Letter entitled Phase 3 Open Items, Mass Participation and Mass Point Spacing, CPSES, Independent Assessment Program, J.0.No. 84042.021, dated February 8, 1985. 4.2 CYGNA Pipe Stress and Pipe Support Review Issues List, Revi-sion 3, and Transmittal Letter No. 84056.106, dated Janu-ary 9, 1987. 5.0 Implementation of the Resolution 5.1 The guidelines for locating the mass points in the pipe stress analysis are included in Section 3.10.6.1 and Attachment 3-7 of CPPP-7, Revision 3. 5.2 Mass point spacing is a review item in the Pipe Stress Analysis Checklist of CPPP-6 and JPPP-9. I l l l l l ] i I 0660Q-1545405-HC4 Q-1 t.

J.'.No. 15454.05-11H REVISION: 1 O DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT I APPENDIX R: HIGH-FREQUENCY MASS PARTICIPATION 1 l (Yh / D. C. Fo's ter R. R. Wrucke ~ Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division _ ~m C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production J h.' W Cliaii Assistant Project Manager - Technical i I $f $b wcC i 'R. P. Klause Project Manager

J.O.No. 15454.05-11H APPENDIX R - HIGH-FREQUENCY MASS PARTICIPATION 1.0 Ba_ckground 1.1 CYGNA's Concern CYGNA, in Pipe Stress Issue 1 and Pipe Support Issue 5 of Reference 4.4, questioned the adequacy of the 33-Hz cutoff fre-quency criteria used in the CPSES pipe stress seismic analysis. 1.1.1 During Phases 1 and 2 of the Independent Assessment Program, CYGNA inquired about the 33 Hz cutoff fre-quency used in the analysis performed by Gibbs & Hill. CYGNA directly addressed the requirement of paragraph II-A-a-(5) of USNRC Standard Review Plan (SRP), Section 3.7.2, which requires investigation of a sufficient number of modes.to ensure participation-of all significant modes. The criterion for suffi-ciency is that the inclusion of additional modes does not result in more than a 10 percent increase in responses. 1.1.2 CYGNA addressed the same concern again during the Phase 3 Independent Assessment Program in the review of the main steam and component cooling water systems. It was discovered that in these systems, the predic-tion of mass participation was insufficient by using a cutoff frequency of 33 Hz. 1.2 TU Electric's Response TU Electric developed three independent analytical approaches to address the high-frequency mass participation, as follows: 1.2.1 Run the seismic analysis without a frequency cutoff, thereby accounting for all seismic modes and a 100-percent mass participation. 1.2.2 Run the seismic analysis up to a cutoff frequency of 33 Hz. In addition, run a static analysis for the ZPA (zero period acceleration) loadings. Compare the two, and use the maximum results. 1.2.3 Use a refined computer program to account automati-cally for the higher order modes, and account for the total system mass. i I 0660R-1545405-HC4 R-1 __________-____L

J.0.No. 15454.05-11H q i 1.3 Gibbs & Hill Evaluation i Based on these approaches, Gibbs & Hill reanalyzed 205 of 271 large bore piping stress problems to address high frequency mass participation. All supports (a total of 5,646) contained j in the 205 piping stress problems were also checked. The con-clusion drawn from the reevaluation by G&H was that the effect i of missing mass participation is inconsequential on the exist-ing piping analysis and support design. 2.0 SWEC's Understanding of the Issue The 33 Hz c'utoff frequency used by Gibbs & Hill in the pipe stress seismic analysis may not meet the acceptance criteria of SRP 3.7.2, paragraph II-A-a-(5). 3.0 SWEC Action Plan to Resolve the Issue 3.1 Review Typical CPSES Piping Systems SWEC reviewed seismic responses of typical CPSES piping stress problems and determined that due to the stiffness of the CPSES piping systems, a high-frequency mass correction is appropriate in some cases. 3.2 Develop Analysis Guideline SWEC developed two analysis options to address the high-frequency mass participation issue. 3.2.1 Perform seismic ARS modal analysis with 50-Hz cutoff frequency, but include a high-frequency mass correc-tion, by using NUPIPE-SW V04/LO2 or later issue. 3.2.2 Perform an equivalent static analysis by using the ZPA values in all three directions. Combine these results by the SRSS method with the results of the seismic analysis with a 50-Hz cutoff frequency that did not include the high-frequency mass correction. 4.0 List of Relevant Documents 4.1 Question.2, CYGNA Communications Reports, J.0.No. 83090 dated { October 5, 1983 1 4.2 CYGNA Letter No. 84042.021, Phase 3 Open Items, Mass Partici-pation and Mass Point Spacing CPSES Independent Assessment Pro-gram, dated February 8, 1985, J.O.No. 84042 4.3 Section 3.7.2, Seismic System Analysis, U.S. Nuclear Regulatory Commission, Standard Review Plan, NUREG-0800, Revision 2, July 1981 l l 0660R-1545405 HC4 R-2

J.O.No. 15454.05-11H 4.4 CYGNA Pipe Stress and Pipe Support Review Issues List, Revi-sion 3, CYGNA Letter No 84056.106 dated January 9, 1987 l 5.0 Implementation of the Resolution 5.1 The high-frequency mass participation criteria has been speci-fled in Section 3.10.6.8 of CPPP-7. 5.2 NUPIPE-SW, V04/LO2, was updated to account automatically for f the high-frequency mass correction. 5.3 High-frequency mass correction is included as a review item in i the Pipe Stress Analysis Checklist, Attachment 9-9 and 9-8 of j CPPP-6 and CPPP-9, respectively. l i i a 0660R-1545405-HC4 R-3 3

J.0.No. 15454.05-11H REVISION: 1 a DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION . STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT - APPENDIX S: FLUID TRANSIENTS l / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division j C. A. Fonseca I Project Engineer - Unit 2 Assistant Project Manager - Production h f-A.'W.VCh'an' Assistant Project Manager - Technical Snw R. P. Klause Project Manager n / I l I i i ) i A

J.0.No. 15454.05-11H APPENDIX S - FLUID TRANSIENTS

1.0 Background

Fluid transients are occasional mechanical loads that should be con-sidered in stress evaluation of ASME Classes 2 and 3 piping. The Gibbs & Hill (G&H) pipe stress analysis for CPSES considered fluid transients on several of the critical systems. The issue of adequa-cy or completeness of the fluid transients that were considered, including the support stability issue (Appendix D), was addressed by TES in Reference 4.2. 2.0 SWEC's Understanding of the Issue Fluid transients should be adequately considered in the pipe stress evaluations of critical CPSES piping systems. 3.0 SWEC Action Plan to Resolve the Issue 3.1 Specific fluid transients have been identified by SWCC and sum-marized in Attachment 1 to CPPP-19. SWEC has identified these transients by following the guidtace given in NUREG-0582 by using SWEC's past experience with other PWRs, and by assessing an overall review of the CPSES system flow diagrams. Addi-tionally, SWEC system engineers are reviewing the piping system operating components which could produce significant fluid transients, such as quickly opening or closing control valves, relief valve discharge, or pump startup or trip. The final fluid transients being considered for CPSES requali-fication will be documented in the System Information Documents (SIDs) as described in CPPP-10. Criteria for evaluation of these fluid transient loads are de-scribed in CPPP-7. The applicable fluid transient analysis and the resulting time-history forcing functions are being included in the piping requalification program. 4.0 List of Relevant Documents 4.1 G&H Specification No. 232S-MS-200, Rev. 4, dated June 29, 1984, Design Specification for all ASME Section III, Code Class 2 & 3 Piping, for CPSES-1 and 2. 4.2 TES draft Letter No. 6216-7 dated February 21, 1985, from D. F. Landers to V. S. Noonan, Director, Comanche Peak Project, U.S. Nuclear Regulatory Commission, which transmitted Technical Report No. TR-6216B, Preliminary Consulting Report on Comanche Peak Steam Electric Station - Piping and Support Design 5.0 Implementation of the Resolution CPPP-7, Revision 3, Section 3.4.5.5 requires that fluid transient loadings be considered for each system, to be identified in the spe-cific SIDs as described in CPPP-10. CPPP-7, Revision 3, Attach-ment 3-1, specifies the procedures used to evaluate piping fluid 0660S-1545405-HC4 S-1

J.0.No. 15454.05-11H transients. The fluid transient loading design attribute is includ-ed in the pipe stress checklist in CPPP-6 and CPPP-9. al 9 / 0 i l t 0660S-1545405-HC4 S-2 t A

J.O.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTl'R ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX T: SEISMIC EXCITATION OF PIPE SUPPORT MASS D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit i Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. W. Chan Assistant Project Manager - Technical k h ttec / R. P. Klause Project Manager

J.O.No. 15454.05-11H APPENDIX T - SEISMIC EXCITATION OF PIPE SUPPORT MASS 1.0 Backgroup 1.1 CASE stated that the effect of seismic acceleration of the sup-port steel (i.e., self-weight excitation) was not included in the design cf the CPSES pipe support assembly structure. The loads from seismic acceleration of the support steel and hard-ware have not been included in the design loads as is required by the ASME Code and the CPSES FSAR. 1.2 The NRC Staff / SIT report stated that all small bore pipe sup-ports were designed by PSE, and adequate seismic accelerations of the support steel were considered in the design of small bore piping and supports. The NRC Staff / SIT report also stated that large bore pipe sup-ports were primarily designed by ITT Grinnell and NPSI. 1.3 TU Electric contended that for large bore pipe supports, the self-weight excitation loads are insignificant in comparison to the design loads imposed by the piping. To confirm that as-sumption, TU Electric randomly selected approximately 400 sup-ports. From this random sample, 23 enveloping case supports were selected and reanalyzed in detail. A separate reanalysis was performed by NPSI on 13 worst-case supports originally designed by NPSI. The conclusion from both the studies is essentially the same, i.e., the seismic self-weight excitation loads are negligible. 1.4 The NRC Staff / SIT evaluated the calculations performed by both TU Electric and NPSI in detail. On the basis of its review of the reanalysis, the NRC Staff / SIT ccncurred with TU Electric's conclusion that 1) in a majority of cases, additional loads re-sulting from self weight excitation are negligible, and 2) in no case will'the inclusion of the loads result in overstressing the support structure. The NRC Staff / SIT concluded that this concern does not present a safety issue and considered this concern resolved. 1.5 CASE responded to the NRC Staff / SIT's position that the sup-ports were modeled as rigid, but are actually Idss rigid when the analysis includes the support connections and all support components. CASE cited the testimony cf TU Electric's witness Dr. Chang, wherein it was stated that the support connections of Richmond inserts and A307 bolts (CPSES actually installed SA-36 bolts) deflect a considerable amount under small loads. As in the NRC Staff / SIT report, the NRC Staff / SIT and TU Electric stated that the supports were assured to be rigid. But since there are oversized holcs and a considerable amount of deflection with the Richmond inser; sad SA-36 bolt con-nection, it cannot be rigid. Therefore, CASE contended that P 0660T-1545405-HC4 T-1

J.O.No. 15454.05-11H TU Electric's assumption of rigid supports is without a valid technical basis. Another factor is the effect of individual component stiffness on the effective stiffness of the support assembly. The ' contributors include the flexibility of the anchor bolts, base plate flexibilities, and the flexibility of the standard componenta such as struts and snubbers. 2.0 SWEC's Understanding of the Issues [ The self-weight excitation load of the supports should be cor.sidered in the support design. 3.0 SWEC Action Plan to Resolve the Issues I 3.1 Seismic acceleration of pipe support mass (self-weight excita-tion) is evaluated for all pipe supports with frames on seismic systems. 3.2 This load is considered negligible on nonframe supports and will be ignored. 3.? The response of the support in each direction is considered the result of separate = odes. Consequently, the resulting loads / stresses from the three directions are combined by the SRSS method. Likewise, these loads / stresses are combined by the SRSS method with the loads / stresses resu' ting from the ceismic pipe loads. The combined SRSS effect of the seismic pipe load and the seis-mic support mass load are considered to be the seismic inertial loads and are combined with other support loads / stresses as indicated in Table 4.7.2-1 of CPPP-7. 4.0 L,ist of Relevant Documente 4.1 CASE's Proposed Findings of Fact and Conclusions of Law, Sec-tion X, dated August 22, 1983 4.2 NRC Inspection Report 50-445/82-26 and 50-446/82-14, dated Februa ry 14, 1983 (NRC Staff Exhibit 207, pages 34, 35,_and 36) l 5.0 Implementation of the Resolution i The procedure to include the effects of pipe support self-weight excitation in the pipe support evaluation has been incorporated in CPPP-7, Revision 3 as Attacliment 4-21. l f 1 0660T-1545405-HC4 T-2 j

H J.O.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ETACTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT . GENERIC ISSUES REPORT APPENDIX U: LOCAL STRESS IN PIPE SUPPORT MEMBERS rW Y D. C. Foster R. R. Wrucke Chief Engineer-Project Engineer - Unit 1 Engineering Nechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production l A. W. Chan Assistant Project Manager - Technical l $bs'tG& R7 P. Klause ' Project Manager 1 1 ll

APPENDIX U - LOCAL STRESS IN PIPE SUPPORT MEMBERS

1.0 Background

1.1 CASE raised the concern that TU Electric has not considered the local stress on a tube steel member that is induced by an at-tached support component, such as a beam bracket, lug, or tube steel. CASE stated that the AWS Code Section 10.5 provides an explicit method for evaluating these effects in stepped and matched tube connections. The AWS method specifies a reduction in the shear allowable to quantify the combined shear and bending capacity of the top chord and the crippling capacity of the sidewalls of the main tube member. CASE alleged that the ASE Code does not address local stress evaluation. 1.2 The NRC Staff agreed with CASE that the ASME Code does not explicitly address local stress, but contends that the pipe support designer must give appropriate consideration to local stress when using tube steel. However, the NRC Staff does not maintain CASE's position that the AWS Code provides the only appropriate method for the evaluation of local stress. TU Electric's practice has been to assess these stresses on a case-by-case basis, as deemed appropriate by the engineer. l 'Ihe NRC Staff reviewed 100 vendor-certified supports and found that the local effect of these stresses had been considered. The most common method of assessment was the local failure approach from AWS Section 10.5.1. ITT Grinnell used its own i procedure, which ir based on the AWS approach. 1.3 CYGNA investigated local stress with a comparison of the con-nection fillet weld to the shear stress. It concluded that, asruming the fillet weld is properly sized, if the tube wall thickness is equal to or greater than the fillet veld size, local stresses in the tube wall will be satisfactory. This was based on a weld allowable of 18 ksi. CYCNA also investigated numerous supports, and in all caces found the local stress to be acceptable. 1.4 CASE also raised the concern that short structural members were incorrectly analyzed in full flexure. CASE stated that more localized stress distribution due to plate behavior would result. 2.0 SVEC's Understanding of the Issues 2.1 Local stress in tube connections, which is addressed in the AVS Code Section 10.5 but not explicitly in the ASME Code, needs to be considered in the requalification of CPSES pipe supports. l 0660U-1545405-HC4 U-1 j

2.2 The local stresses in tube steel walls induced by nuts on bolts and nuts on Richmond inserts, rear brschets, and other attach-ments need to be considered in the requalification of CPSES pipe supports. 1 2.3 The stress analysis in short members and their welds must be properly assessed. i 3.0 SWEC Action Plan to Resolve the Issues 4 3.1 A procedure to evaluate local stress on pipe support members based i on the methods of AWS Code Section 10.5, including yield line analy-sis, and the ASME and AISC Codes, as appropriate, has been developed for inclusion in CPPP-7. It addresses: 1. Tube-to-tube connections both stepped and size on size (AWS) 2. Brackets welded to tube steel (AWS) 3. Nuts bearing on tube steel walls (ASME/AISC) 4. Washer plate design (ASME/AISC) 1 5. Rear brackets on cap plates welded to the end of tube steel (ASME/AISC) 6. Web crippling of tube steel under pipe line contact (AWS) 7. Web crippling and flange bending of I-shapes (ASME/AISC) 8. Stress distribution in short members (ASME/AISC) 9. Lugs bearing on tube steel walls (AWS) 10. Branch members other than tube steel or rear brackets attached to tube steel (AWS). ( 4.0 List of Relevant Documents 4.1 CASE's Proposed Findings of Fact and Conclusions of Law, [ Section IX, August 22, 1983 4.2 Affidavit of J. C.

Finneran, Jr.,

Regarding Consideration of Local Displacements and Stresses, June 18, 1984 4.3 CASE's Answer to Applicants' Statement of Material Facts as to Which There is No Geniune Issue Regarding Consideration of Lo-cal Displacements and Stresses, August 27, 1984. 4.4 Applicant's Reply to CASE's Answer to Applicants' Motion for Summary Dispos,ition Regarding Local Displacements and Stresses, September 28, 1984. i 0660L-1545405-HC4 U-2 l

4.5 CASE's Answer to Applicant's Reply to CASE's Answer to Appli-cants' Motion for Sumnary Disposition Regarding Local Displacements and Stresses, October 9, 1984. 4.6 NRC Staff Response to Applicant's Motion for Summary Dis-position on AWS and ASME Code Provisions on Weld Design, 1 November 2, 1984 4.7 CASE's Answer to Applicants' Motion for Summary Disposition of Certain CASE Allegations Regarding AWS and ASME Code Provisions Related to Design Issues, August 6, 1984 4.8 Affidavit of J. C. Finneran, Jr., R. C. Iotti, and J. D. Ste-venson Regarding Allegations Involving AWS Versus ASME Code

Provisions, May 15, 1984 l

4.9 Transcript of Proceedings Before the United States Nuclear Reg-1 ulatory Commission, Washington, DC, in the Matter of Meet.ing to l Conduct Feedback Discussions with Messrs..Walsh and Doyle Re Concerns About the Comanche Peak Plant Held March 23, 1986 5.0 Implementation of the Resolution CPPP-7, Revision 3, Section 4.3.3.1, specifies, the requirements to evaluate the local stress in pipe support members. The procedure for Items 1 through 10 discussed in Section 3.0 for the evaluation of local stresses in pipe supports has been incorpo-rated into CPPP-7, Revision 3, Attachment 4-13. 0660U-1545405-HC4 U-3 I ls

Revision: 1 DATE: 07/24/87 J.0.No. 15454'.05-11H TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER' ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX V: SAFETY FACTORS (f f D. C. Foster R. R. Wrucke . Chief Engineer Project Engineer - Unit 1 Engineering. Mechanics Division f" - -;_ =ese, C. A. Fonseca , Project Engineer - Unit 2 Assistant Project Manager - Production -- _/ A.'W. Chan Assistant Project Manager - Technical Ah!'a.a - - l R. P. Klause Projecttianager i l 1 l-l l I _______.._________h._

J.O.No. 15454.05-11H j l 1 APPENDIX V - SAFETY FACTORS 1.0 I,ackground l l 1.1 CASE stated that industry practice of not expressly factoring small potential loads into design calculations is not supported by adequate CPSES factors of safety (Reference 4.1). 1 1 CASE stated that TU Electric was avoiding the issue by not ad-dressing effects such as anchor bolt gaps on a structure's be-havior under seismic loading conditions. CASE stated that i TU Electric was neglecting the consequences of small potential 1 loads during normal operation and that the CPS,ES safety factors have already been eroded by various allegations of poor and insufficient design practices. 1.2 TU Electric addressed this concern by categorizing the factors CASE is focusing on as those safety factors associated with margins inherent in the ASME or AISC Codes or termed " capacity" safety factors. There are two other safety factors already built in within the CPSES " design input definition" and " method of analyses." It is the cumulative effect of safety factors in all three categories that lends credence to the practice of not expressly factoring small potential load contributors, such as anchor bolt gap effects and self-excitation of supports into design calculations. The real question is the adequacy of CPSES design processes ~ to ensure the pressure boundary integrity of the piping systems. TU Electric stated that there are a few key design parameters that affect safety of the plant, such as the strength of mem-bers, the frequency characteristics of the piping systems, the ability to deform inelastically and absorb energy, and the ability to redistribute loads and stresses throughout the sys-tem. CPSES piping systems are virtually indistinguishable from other nuclear plants, and past history indicates that structur-al systems of this type perform very well indeed, even under { loads far exceeding their original design basis. TU Electric also cited examples from past documented events, including seismic events, and concluded that the observed behavior of the structures being verified by the engineering assessment den on-strated the built-in conservatism in the design criteria of CPSES piping systems. 2.0 SWEC's Understanding of the Issues All generic technical issues must be resolved before CPSES could invoke the inherent design margin (safety factor) accumulated from tha built-in conservatism in codes, input, and regulatory positions that typically provide sufficient margin so that small potential load variations that may result from acceptable industry practice and design tolerances may be neglected. 0660V-1545405-HC4 V-1

J.O.No. 15454.05-11H 3.0 SWEC Action Plan to Resolve the Issues SWEC has evaluated all the generic technical issues for inclusion into the CPPP-7 design criteria for the CPSES requalification ef-fort. With all generic technical issues appropriately addressed, there is sufficient margin to justify the neglect of small potential load variations during normal operation. 4.0 List of Relevant Documents 4.1 CASE's Proposed Findings of Fact and Conclusions of Law, Section I, dated August 22, 1983 4.2 Affidavit of J. C. Finneran, R. C. Iotti, and R. D. Wheaton Regarding Safety Factors dated May 20, 1984 4.3 Affidavit of R. D. Wheaton, J. C. Finneran, and R. C. Iotti in Reply to CASE's Partial Answer to Applicants' Motion for Summa-ry Disposition Regarding Safety Factors dated November 1,1984 4.4 CASE's Partial Answer to Applicants' Statement,of Material Facts as to Which There is No Genuine Issue Regarding Safety Factors dated August 27, 1984 5.0 Inrplementation of the Resoiution No additional action is required, since each generic technical issue has been evaluated and its resolution has been incorporated into CPPP-7, Revision 3 as required. l 1 l 0660V-1545405-HC4 V-2 l [

' J.O.No. 15454.05-11H-Revision,1 DATE: 07/24/87 t TU ETECTRIC~ COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX W: A36 AND A307 STEEL / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division D &re4A J C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. K.Chan Assistant Project Manager - Technical / R. P. Klause Project Manager l ...._____________..__________j

J.O.No. 15454.05-11H APPENDIX W - SA-36 ANI) SA-307 STEEL '1. 0 Background 1.1 The Atomic Safety Licensing Board (ASLB) requested that TU Electric prer'ide testing data of SA-36 and SA-307 steel to de-termine whether materials used in the following tests were rep-resentative of materials used in CPSES and to assess the impact of material properties on the establishment of allowebles: Tests performed by Westinghouse on cinched-down U-bolt assemblies. Tests conducted by ITT-Grinnell regarding 'i-bo l ts acting as two-way restraints. The following tests conducted by TU Electric on Richmond in-serts (Reference 4.2). Test A) March 1983 - Shear tests of Richmond inserts Tes't B) April 1984 - Shear and tension tests of Richmond inserts Test C) May 1984 - Richmond and tube steel loaded in shear and tension 1.2 The Board questioned whether allowables are taken from actual material properties, as indicated on certified material test reports. TU Electric demonstrated that allowables are taken from the ASME Section III Code which specifies minimum proper-ties, not values of tested site materials. 1.3 CASE stated that SA-36 and SA-307 material are similar and that the AISC code prohibits the use of A-307 material in friction connections. Therefore, CASE concluded that SA-36 U-Bolts and threaded rod for Richmond inserts cannot be used in friction Connections. 1.4 Since the AISC and ASME codes do not recommend the use of A-307 material when subject to a high number of loading cycles, the ~NRC staff was concerned with the fatigue. life of SA-36 material used as U-Bolts and threaded rod for Richmond inserts. 2.0 SWEC's Understanding of the Issues 2.1 The material for the, target component used in the above-described tests must be representative of the actual material used onsite to ensure that the test results are meaningful. 2.2 The material allowables used in the design assessment of pipe supports at CPSES must be derived from the code minimum yield strength. 0660W-1545405-EC4 W-1 i U

J.O.No. 15454.05-11H l l 2.3 AISC Code 7th Edition Table 1.5.2.1 prohibits the use of SA-307 as bolting material in friction connections. SA-36 and SA-307 l materials are similar. ASME III Code Inquiry NI86-030 (Refer-ence 8.6) clarifies that cinched U-bolts are not friction con-nections. However, since the U-bolt design relies on friction to provide stability, the bases of the AIGC prohibition need to be understood and addressed. 2.4 SA-36 material used in cinched U-Bolts, U-Bolts as two-way re-straints, and as rod threaded into the Richmond insert are sub-l ject to load cycling, which must be considered in the qualification. ASME III Appendix XVII Table XVII-3230-1, foot-note 4 and AISC 7th edition Appendix B Table B2, footnote 4 state' "Where stress reversal is involved, use of A307 bolts is not recommended." Material fatigue is the primary concern. 3.0 SWEC Action Plan to Resolve the Issues 3.1 Test Materials The U-bolts used by ITT and Westinghouse were SA-36 material. Cinched U-bolts with struts and snubbers are not used at CPSES. U-bolts used as 2-way restraints were obtained from standard component stock supplied by NPSI and/or ITT Grinnell. A review of the load capacity data sheets (LCDs) and certified design reports (CDRs) verifies that SA-307 material was not used for the U-bolt and that SA-36 material or better was used. The bolts / threaded rod used in the Richmond insert shear and tension test (Test A and B) were A490/SA-193 Gr. B7 (high strength). This was intended to ensure that the Pichmond in-sert and not the bolt would govern the test results. This was an appropriate measure, since the purpose of the test was to determine the insert capacity. The use of SA-36 rod in the Richmond insert / tube steel tests (Test C) provided insight into the behavior of the Richmond insert / tube joint. The materials used in the above tests were manufactured to the same ASTM standards as similar components used onsite. l -5 of CPPP-7 provides load capacities for SA-36 and SA-193 Gr. B7 threaded rod. If SA-307 threaded rod is identi-l fied on the support drawing, it will be replaced. 3,2 Design Allowable Material design allowables for linear components, such as SA-36 U-bolts and SA-36 th2maded rod, are determined from the ASME Code minimum vield strength. j l l '0660W-1545405-HC4 W-2

J.O.No. 15454.05-11H 3.3 Use of SA-36 Material in Friction Connections Cinched U-bolts are not being used at CPSES. U-bolts as two-way restraints and Richmond insert connections are not preloaded and are designed as bearing connections. 3.4 SA-36 Material Subject to Cyclic Load A6ME III, Appendix' XVII, Table XVII-3230-1, Footnote 4, and AISC 7th Edition, Appendix B, Table B2, Footnote 4 state, "Where stress reversal is involved, use of A30/ bolts is not recommended." Both sections define the lower bound value for consideration of stress cycles as 20,000. Since SA-307 and SA-36 materials are similar, the concern is that the threaded portion 'may suffer fatigue failure under cyclic loading when subject to stress reversals. The U-bolt as a two-way restraint and Richmond inserts are sub-ject to reversing stress fields due to seismic and fluid tran-sient loads. J The SA-36 U-bolts used as two-way restraints as well as the threaded rod used sith Richmond insert tube steel joints, are designed as ASME III linear NF support components in accordance with Appendix XVII and AISC, respectively. SWEC has demon-strated that the number of equivalent stress cycles for these components is less than 7,000. Therefore, fatigue is not a relevant concern as defined in these codes. j 3.5 Use of Test Results Although many tests were performed in support of previous tes-tin.ony and affidavits, not all tests are being used in support of the resolution of generic technical issues. The use of the tests results mentioned in Section 1.1 is discussed below. 3.5.1 U-Bolts as Two-Way Restraints The ITT Grinnell tests were used to gain an understanding of the U-bolt mechanism as a t'wo-way restraint. Load ca-pacities were not derived from these tests but from ASME Code minimum yield strength as discussed in Appendix F. 3.5.' Richmond Insert Tests Insert allowables were obtained from the April 1984 tests. However, appropriate adj ustments in the test values were made to reflect the design concrete strength of 4000 psi l and a factor of safety of 3 for normal, upset, and emer-gency conditions, and a factor of safety of 2 for faulted l condition. An understanding of the behavior of the tube steel insert joint was also derived from the TU Electric tests. l 1 j 0660W-1545405-HC4 W-3 / a

J.O.No. 15456.05-11H 4.0 List of Relevsnt Documents 4.1 CASE's Proposed Findings of Fact and Conclusions of Law, dated August 22, 1983. 4.2 Affidavit of John C. Finneran, Jr., Robert C. Iotti, and Peter Deubler Regarding Design of Richmond Inserts and Their Applica-tion to Support Design, dated June 1, 1984. 4.3 Affidavit of R. C. Iotti and J. C. Finneran, Jr., Regarding Board's Request for Information Concerning A-36 and A-307 Steel, dated December 5, 1984. 4.4 Affidavit of Robert C. Iotti and John C. Finneran, Jr., Regard- ~ing the Licensing Board's December 19, 1984, Memorandum, dated January 7, 1985. 4.5 CASE's Fourth Motion for Summary Disposition to Disqualify the Use of SA-307 and SA-36 Threaded Parts, dated January 14, 1985. 4.6 ASME III Code Inquiry NI86-030 "Section III, Division 1, NF-3324.6(a)(3)(b) Friction Type Joints, NF-3324.6(a)(4) Slip Resistance, Friction Type Joints, NF-3225.4, Friction Type

Joints, 1983 Edition with the Winter 1985 Addenda, dated June 25, 1986.

4.7 CASE's Partial Answer to Applicants' Statement of Material Facts Relating to Richmond Inserts as to Which There are No Material Facts, September 10, 19J4. 5.0 Implementation of the Resolution 5.1 Design allowables The allowable stresses for the material used in the CPSES sup-ports are determined from the minimum yield strength specified -by the code in Section 2.2 of CPPP-7. i 5.2 Use of SA-36 Material in Friction Connections In accordance with CPPP-7, Revision 3, Section 4.2.5.1, c*nched U-bolts will not be used at CPSES. i 5.3 SA-36 Material Subject to Cyclic Loads SA-36 material used in U-Bolts and threaded rod for Richmond inserts (see Appendix A) will not experience fatigue failure, since the number of stress cycles is less than 7,000 and the U-bolts are designed as ASME III linear NF ~ component in accor-dance with Appendix XVII, and the threaded rod for Richmond inserts is design.ed to AISC. 0660W-1545405-HC4 W-4

J.O.No. 15454.05-11H 5.4 Use of Test Results l l Section 3.5 of this appendix discusses the use of test results that affect the resolution of this generic issue. 1 1 ) l i 05604-1545405-HC4 W-5

J.O.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU EIICTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINE 2 RING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX X: U-BOLT TWISTING l /$YI Yll b D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. W. Chan Assistant Project Manager - Technical A $ Ali: W R. P. Klause Project Manager I ._.m.b

APPENDIX X - U-BOLT TWISTING

1.0 Background

As discussed in Appendix D, Pipe Support / System Stability, a trapeze sup-port with U-bolt is considered to be potentially unstable, since it may move arially along the pipe and/or rotate around the pipe creating a three-pin linkage system. In addition to stability, the NRC Staff noted that out-of plane rotation of the crosspiece may result when the struts are in compression. This rotation would induce twisting on the U-bolt, for which it was not de-signed. U-bolts on trapeze supports were cinched. Therefore, TU Electric com-mitted to analyze / design the trapeze as a rotational as well as a trans-lational restraint. However, as discussed in Section 3.1.3 of Appendix L, all U-bolt trapeze supports will be modified. Modification will provide for axial stabili-ty, no rotational (torsional) restraint of the run pipe, and the poten-tial for crosspiece twisting will be addressed. 2.0 SWEC's Understanding of the Issue U-bolt trapeze support modifications must address the potential for the rotation of the crosspiece that vould result in twisting of the U-bolt. 3.0 SWEC's Action Plan The issues of stability, rotation restraint of the pipe, and the twisting effect on U-bolt trapeze supports were addressed. SWEC's review indicated that extensive engineering iterations were re-quired to demonstrate the ability of this type of support to satisfy all three concerns. SWEC judged it to be more expeditious to modify the U-bolt trapeze supports as discussed in Sectica 3.1.3 of Appendix L, and CPPP-7, Revision 3, Attachment 4-0. 4.0 List of Relevant Documents 4.1 Affidavit of John C. Finneran, J, Regarding Stability of Pipe Supports cad Piping Systems, June 17, 1984 4.2 CASE's Motions and Answer to Applicants for Summary Disposition Regarding Stability of Pipe Supports, October 15, 1984 l 4.3 Testimony of N. H. Williams in Response to CASE Question of February 22, 1984, to CYGNA Energy Services 4.4 Letter to Mr. J. B. George of TU Electric from N. H. Williams of CYGNA in Reference to S tabil i ty of Pipe Supports, Febru-l ary 19, 1985 0660X-1545405-HC4 X-1 --____a

i 4.5 Letter to Mr. J. B. George of TU Electric from N. H. Williams of CYGNA in Reference to Stability of Pipe Supports, April 30, 1985 4.6 CASE ' s - Proposed Finding of Fact and Conclusions of Law, Section III, dated August 22, 1983 5.0 Implementation of the Resolution In accordance with CPPP-7, Revision 3, Section 4.2.5.1, cinched U-bolts are not used at CPSES. Guidance 'for the modification of U-bolt trapeze supports has been incor-porated in CPPP-7, Revision 3, as Attachment 4-8. l f L l l 0660X-1545405-HC4 X-2 ___- -- - __ -____ _ _ a

J.O.No. 15454.05-11H REVISION: 'l - DATE: 07/24/87 TU ELECTRIC I COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S G C S P T 1 APPENDIX Y: FISHER / CROSBY VALVE MODELING/ QUALIFICATION ht$h /fW D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production M A. W. Chan Assistant Project Manager - 1 Technical / /1 Af A%. u-R. P. Klause Project Manager a

J.O.No. 15454.05-11H APPENDIX Y - FISHER / CROSBY VALVE MODELING/ QUALIFICATION

1.0 Background

1.1 Crosby Valves The Crosby valve is the main steam (MS) safety relief valve (SRV). The valve has a double ported outlet configuration. Five of these valves are located along the MS line that dis-charges into vent stacks. CYGNA, in Issue 17 of Reference 4.7, stated that by assuming a 55/45 split in the flow instead of the 60/40 suggested by Crosby Valve as general practice, the torque on the Main Steam Pipe is halved. CYGNA raised a concern that the worst load condition of multi-pie valves opening and discharging was not considered by TU Electric. 1.2 Fisher Valves l The Fisher valve is a control valve that is used to control MS flow by relieving steam to the atmosphere. The Fisher talve body was supported by two snubbers.

CYGNA, in Issue 6 of Reference 4.7, observed that the snubbers on the Fisher ' valve operators were not qualified for the as-built loads.

This issue led to questioning whether the valve itself was capable of transmitting / withstanding these loads and still maintaining operability. 1.3 Flexible Valves CYGNA, in Issue 18 of Reference 4.7, has questions on the mod-eling of " flexible" valves (Frequency (F) < 33 cps). In the review, CYGNA found that valves noted in Reference 4.8 (other than Fisher valves) were the only " flexible" valves within the Gibbs & Hill scope. CYGNA determined that the valve accelera-tions for. those valves were acceptable; however, CYGNA did not j address the modeling of the Fisher valve yoke, which is later-ally supported at the end. If the yoke is modeled much stiffer than it actually is, this may affect the analysis results. 2.0 SWEC's Understanding of the Issues 2.1 The effect of unbalanced loading due to unequal discharge fore-es from steam exiting the SRV ports should be evaluated. The vendor has suggested a ratio of 60:40 for the discharging elbow 3 and venting design. TU Electric analysis used a 55:45 ratio. Compliance with Regulatory Guide 1.67, which requires the worst condition loading design basis of multiple valve actuating com-0660Y-1545405-HC4 Y-1 ____________-____ - __ _ ~

J.O.No. 15454.05-11H f l i binations, is needed. The TU Electric analysis did not consider this requirement. 2.2 The Fisher relief valve branch connection used snubbers to mit-igate the steam discharging load on the valve top-works. The load transmitted to the snubbers must be within the limits of the valve structural capabilities. This load must be addressed in the valve qualification. t l 2.3 The yokes of flexible valves must be properly modeled to prop-erly predict the yoke frequency. 3.0 SWEC Plan te Resolve the Issues 3.1 SWEC discussed the flow distribution of doubled ported SRV with Crosby (Reference 4.6), and Crosby verified that the SRV has an equal (50:50) flow distribution ratio. The original Crost? position of 50:50 flow distribution ratio was stated in Refet-ence 4.5. Apparently, CYGNA had misinterpreted a telephone conversation note (Reference 4.4), in which Crosby suggested that 60:40 load distribution may be used for initial venting design assessment. For conservatism, a 55:45 SRV flow distribution ratio is used to calculate the blowdown force that is applied to the dis-charging elbow and vent stack configuration. 3.2 SWEC evaluated the multiple SRV loading combination issue and concurs that all five valves opening simultaneously must be considered for pipe and support design. Since valves may open in a set or random sequence, those cases are also considered. These cases are addressed by the project system input document (SID) for the MS system including the worst load condition. 3.3 The SWEC requalification of Fisher relief valve branch connec-tion piping model includes the effects of the snubber supports at the valve. The' resultant load transmitted to the valve body through the snubbers is transmitted to Impell Corporation for the qualification of the Fisher valve's structural adequacy and operability. l 3.4 The yokes of flexible valves are modeled to properly predict { the yoke frequency. 4.0 List of Relevant Documents 4.1 CYGNA communications reports dated March 12, 1984, Job No. 84042 and June 12, 1984, same subject 4.2 CYGNA Observation Record PI-00-07 4.3 Tenera Corporation letter to J. Finneran dated October 3,1985, regarding preliminary list of piping and support issues l 1 j 0660Y-1545405-HC4 Y-2

J.O.No. 15454.05-11H 4.4 Tel-con dated October 21, 1976, between Crosby Valve and Gibbs & Hill, J. R. Zahorsky and M. H. Giden, regarding Con-tract No. 2323A, Double-Ported Safety Valves 4.5-Telex from Crosby Valve to Gibbs & Hill regarding Contract No. 2323A, Main Steam Safety Valves, J. P.. Zahorsky to Dr. Kim dated October.12, 1976 4.o Tel-con dated Februa ry 21, 1986, between R. Martin and J. R. Zahorsky of Crosby Valve and W. Wang, A. J. Cokonis, and W. H. Green of SWEC, regarding Crosby double ported relief valve discharge loads. 4.7 CYGNA Pipe Stress and Pipe Support Review Issues List, Revision 3, and Transmittal Letter No. 84056.106 dated January.9, 1987. 4.8 Communications Report between Krishnan/ Ray (Gibbs & Hill) and Minichiell.o (CYGNA) dated June 18, 1984. 5.0 Implementation of the Resolution 5.1 A 55:45 SRV flow distribution ratio is conservatively used to calculate the blowdown force that will be applied to the dis-charging elbow and vent stack configuration. The SID for the main steam piping has been revised to reflect the 55:45 ratio of thrust load. 5.2 The SID identifies design basis for multiple SRV openings, in-cluding five simultaneous valves opening for stress analysis evaluation. The cases evaluated cover all possible circum-stances based on the system design, including the worst load condition. 5.3 Sections 7.4.3 and 7.4.1.3 of CPPP-6/CPPP-9 specify evaluations of items to be transmitted fcr design acceptance. Valves with supports will have both valve accelerations and support loads transmitted to Impell Corporation for qualification, except for Westinghouse-supplied valves, which will be transmitted to Westinghouse. 5.4 CPPP-7, Section 3.10.6.5 addresses the proper valve yoke model-ing of flexible valves. 0660Y-1545405-HC4 Y-3 4

'J O No 15454.05 11H REVISION: 1 2 DATE: 07/24/87 i TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION i' STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX Z: PT. PING MODELING i M D. C. Foster R. R. Wrucke

Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division.

C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production 1 A. W. Chan Assistant Project Manager - Technical b hcc e - R. P. Klause Project Manager 4

J.0.No. 15454.05-11H APPE!IDIX Z - PIPING MODELING

1.0 Background

CYGNA reviewed the G&H calculations and found instances of question-able input parameters. The five pipe stress issues of incorrect input parameters in the pipe stress analysis as stated by CYGNA in Reference 4.3 are as follows: 4 1.1 The wrong pipe wall thickness was used to calculate an allow-able nozzle load (Issue 2). 1.2 Improper stress intensification factors were used (Issue 10). 1.3 Fluid and insulation weights were not included for valves and flanges (I: sue 4). i 1.4 Valve acceleration and flange loads were not always checked in the piping analysis (Issue 21). 1.5 Two piping segments were input to the stress analysis with the incorrect wall thickness (Issue 12). l 2.0 SWEC's Understanding of the Issues CYGNA has identified discrepancies in the pipe stress calculations. 3.0 SWEC Action Plan to Resolve the Issues Project procedures have included checklists to ensure that appropri-ate piping models are created and that adequate review of the input and output is performed. All piping and support calculations, in-cluding the revisions, must follow the SWEC corporate procedures in Engineering Assurance Procedure EAP-5.3. In addition, SWEC trains personnel in the implementation of the pro-cedures. This training is further enhanced by daily contact with the experienced on project technical supervision and frequent off-project independent evaluation. l 4.0 List of Relevant Documents 4.1 TERA Corporation letter dated October 3,1985, to J. Finneran of TUElectric Preliminary List of P,iping and Support Issues. 4.2 CYGNA Observation No. PI-00-01 dated October 6, 1983. 4.3 CYGNA Pipe Stress and Pipe Support Review Issues List, Revision 3, and Transmittal Letter No. 84056.106 dated January 9, 1987. 0660Z-1545405-HC4 Z-1

. 'J'. 0'. No. 15454.05-11H l. 5.0 Implementation of the Resolution ' Project Procedures CPPP-6, CPPP-7,- and CPPP-9 provide guidancs for the proper modeling of piping systems.. SWEC Engineering Assurance Procedure EAP 5.3 provides guidance on the preparation and review of calculations. The SWEC Engineering Assurance Division performs audits of project activities to verify that all of these procedural requirements are met and that the calculation is technically adequate. The combina-tion of the procedures, the procedural controls, and the audits pro-J .vides assurance that calculations are complete and technically adequate. ~ 0660Z-1545405-HC4 Z-2

c ~.- .-l Q. v. s J.0.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 '1 !a { 3

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TU ELECTRIC " i ~ fd COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S !.,-{ LARGE BORE PIPE STRESS AND PIPE SUPPORT Ei ~ ' y(. GENERIC ISSUES REPORT APPENDIX AA: WELDING 9 [.g ' y ^; lp; t. 1.- ~ / D. C. Foster R. R. Wrucke . l" Chief Engineer Project Engineer - Unit I Engineering Mechanics Division C. A. Fonseca 0' ~,.. Project Engineer - Unit 2 ..E fC [ l 'k i

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APPENDIX AA - WELDING

1.0 Background

Various welding concerns that were identified by CASE, CYGNA, and the NRC Staff are as follows: 1.1 Undersized Fillet Welds CYGNA reported in pipe support Issue 21 of Reference 4.15 that the sizes of two fillet welds were found to be less than the minimum requirements of Table XVII-2452.1-1 in Appendix XVII of the ASME Section III Code. 1.2 Penetration Weld Subsurface Cracking There is a potential for subsurface cracking on welds with deep penetration and/or small included angles (below 60 deg). The weld cooling shrinkage may be resisted where the joined surfac-es approach being parallel. Under these conditions subsurface cracking can occur without the crack propagating to the sur-face. Upon loading this subsurface crack may propagate through the weld causing joint failure. 1.3 Fillet Weld Cracking on Trunnions Trunnions with outside diameter (OD) greater than two-thirds of the OD of the pipe to which they attach have included angles which are greater than 135 deg. Fillet welds are typically used, and this will result in a small effective throat. In-cluded angles exceeding 135 deg are not allowed by AWS for prequalified welds. 1.4 Eccentricity of Three-Sided Welds (CYGNA) CYGNA stated in Issue 22 of Reference 4.15 that analyses of three-sided welds have not always considered the eccentricity between the center of gravity of the member and the weld. 1.5 Linear Versus Plate and Shell Weld Design for Base Plates (NRC Staff) The NRC Staff questioned whether it was acceptable to qualify base plate welds to linear analysis requirements. 1.6 Attachment of Base Plates to Building Structures With Both Bolts and Welds (CYGNA) l CYGNA found in Issue 2 of Reference 4.15 no evidence that welded / bolted connections are designed in accordance with para-graph XVII-2442 of Section III of the ASME Code. i 0660AA-1545405-HC4 AA-1

1.7 Crosspiece Trapeze Cover Plate Welds (CYGNA) .CYGNA in Issue 23 of Reference 4.15 observed that shear flow has not always been considered in the analysis of welds attach-ing cover plates to crosspiece members. 1.8 One-Third Increase of Weld Allowable Stress for Emergency and Faulted Conditions The practice of increasing weld allowable stresses by one-third for emergency and faulted conditions was questioned. 2.0 SWEC's Understanding of the Issues Detailed welding configuration and analysic concerns as identified above need to be addressed. 3.0 SWEC's Action Plan to Resolve the Issues 3.1 Undersized Fillat Welds ASME Code Case N-413 eliminates the minimum weld size require-ments of Table XVII-2452.1-1 in the ASME Section III Code. The requirement for a minimum weld size check for welds designed to ASME requirements has been eliminated in CPPP-7, Revision 3. 3.2 Penetration Weld Subsurface Cracking The tendency to d(velop unterline weld cracks stems from the " misuse of a welding process that can achieve deep penetration l or poor joint design. A few preventive measures can ensure l elimination of both of these factors. Limiting the penetration j and the volume of weld metal deposited per pass, through speed I and amperage control, and using reasonable depth of fusion are l both steps in the right direction" (Reference 4.16). At CPSES all pipe support welds were specified to be made by the shielded metal arc welding (SMAW) process in accordance l with Brown and Root Weld Procedure WPS-11032. MC has reviewed WPS-11032 and concluded that it is a quali-l fled procedure which controls the joint design, travel speed, electrode size, and amperage and that the SMKw process is not a i deep penetration process. I Therefore, the potential for centerline weld cracking does not j exist. i 3.3 Fillet Weld Cracking on Trunnions { i All CPSES welds are qualified and inspected to preclude any i cracks in.accordance with ASME requirements, thereby producing sound welds. For the purpose of design, credit will not be taken for portions of welds on included angles which ' exceed 0660AA-1545405-ilC4 AA-2

135 deg. The weld section property is conservatively deter-q mined using the effective throat at 135 deg, which is \\ 76 percent of the throat at 90 deg. The maximum strain on any excluded portion of the weld (136 deg to 180 deg) equals 1.5 times the strain at 135 deg. This strain will not cause crack-I ing of sound welds. Therefore, fillet weld cracking on trunnions will not occur. 3.4 Eccentr4 city of Three-Sided Weldc CPPP-7, Revision 3, -2, paragraph 3.1.2 requires that the t. eccentricity between the center of gravity of the mem-ber and the weld be considered. 3.5 Linear Versus Plate and Shell Weld Design for Base Plates ASME Section III, Subsection NF-1230 allows the use of either plate-and-shell or linear-type support rules for the design of welds connecting linear and plate and shell elements. 3.6 Bolted and Welded Connections CPPP-7, Attachment 4-2, paragraph 3.1.3 requires that the weld be designed for the entire shear force in accordance with ASME III, paragraph XVII-2442. 3.7 Crosspiece Cover Plate Welds CPPP-7, Revision 3, -2, paragraph 3.1.5 requires that members which use cover plates for strength purposes will have the plate-to-member attachment welds qualified for shear flow. 3.8 One-Third Increase in Allowable Weld Stress for Emergency and Fa_ulted Conditions 3.8.1 A one-third increase in allowable weld stress for emergency and faulted conditions is acceptable. In the ASME Code, both NF 3231.1(b), Design of Linear Type Supports by Analysis for Class 1 Component Sup-

ports, and Appendix XVII-2110(a),

Linear Elastic Anclysis, address an allowable stress increase for emergency and faulted conditions. Because they are general comments, they apply to weld designs which are covered in these sections. The emergency condi-tion is stated as having a one-third allowable in-crease. Both sections refer to Appendix F for the faulted condition, where the factor is always greater than one-third. 3.8.2 AISC has allowed the one-third increase since the 7th edition. 0660AA~1545405-HC4 AA-3

3.8.3 Correspondence from K. Ennis, Assistant Secretary of ASME, to W. M. Eifert of SWEC, dated September 25, 1985, confirms this position (Reference 4.14). 4.0 List of Relevant Documents 4.1 N. H. Williams (CYGNA) letter to J. B. George (TV Electric), Design of Welded / Bolted Connections, 84042.024, dated January 28, 1985 4.2 Communications Report between Rencher (TU Electric) and Minichiello (CYGNA) dated March 21, 1984, Irem 1.c 4.3 L. M. Poppelwell (TU Electric) letter to N. H. Williams (CYGNA) dated April 19, 1984 4.4 CYGNA Phase 3 Final Report, TR-84042-01, Revision 1, Observa-tion PS-04, 05, 06, and 07 4.5 Communications Report between Rencher (TU Electric) and Minichiello (CYGNA). dated May 16, 1984, Item 5 4.6 L. M. Poppelwell (TU Electric) letter to N. H. Williams (CYGNA) dated June 8, 1984, Item 31 4.7 Communications Report between Grace (TU Electric) and Minichiello (CYGNA) dated May 22, 1984, Item 1 4.8 L. M. Poppelwell (TU Electric) letter to N. H. Williams (CYGNA) dated June 8, 1984, Item 32 4.9 N. H. Williams (CYGNA) letter to J. B. George (TU Electric), Box Frames with 0 Gap, 84042.023, dated January 28, 1985, Item 3 of the Attachment 4.10 N. H. Williams (CYGNA) letter to J. B. George (TU Electric), Mass Participation and Mass Point Spacing, 84042.021 dated February 8, 1985, Pipe Support Review Item 5 4.11 Communications Report between Finneran (TU Electric) and Williams /Minichiello_(CYGNA) dat'ed July 11, 1984, Item 1 4.12 Communications Report Detween Finneran (TU Electric) and Minichiello (CYGNA) dated July 11,'1984 4.13 L. M. Poppelwell (TU Electric) letter to N. H. Williams (CYGNA) dated July 12, 1984 4.14 Letter from K. Ennis, Assistant Secretary of

ASME, to W. M. Eifert of SWEC dated September 25, 1985.

4.15 CYGNA Pipe Support Review Issues List Revision 3, and Transmit-tal Letter No. 84056.106 dated January 9, 1987. 0660AA-1545405-HC4 AA-4

4.16 Design of Welded Structures, Omer W. Blodgett, 1966. 5.0 Implementation of the Resolution The detailed analysis procedure of welds is incorporated in Section 4.4 and Attachment 4-2 of CPPP-7, Revision 3. 0660AA-1545/05-HC4 AA-5

J.O.No. 15454.05-11H REVISION: 0 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER. ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APFENDIX BB: ANCHOR BOLTS /EMBEDMENT PLATES / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production _A. 7.'Chan Assistant Project Manager - Technical .1,1 7 bl Out u R. P. Klause Project Manager mm -i-----i-m---------m

J.O.No. 15454.05-11H APPENDIX BB - ANCHOR BOLTS /EMBEDMENT PLATES 1.0 background CYGNA in Reference 4.1 identified seven concerns with embedment plate, anchor bolt, and base plate designs at CPSES as follows: 1.1 Embedment Attachment Spacing l CYGNA, in pipe support Issue 9, noted that CYGNA has not seen evidence that attachment spacing between embeament plates was checked at CPSES. 1.2 Through-Bolt Structural Embedments Loads CYGNA, in pipe support Issue 10, noted that CYGNA cannot find l written evidence documenting that as-built loads from pipe sup-ports that use through-bolts were transmitted to the TU Elect-ric Civil Group. 1.3 Base Plate Edge Distance CYGNA, in pipe support Issue 11, alleges that the anchor bolt l edge distance tolerances could result in a 15-percent increase in base plate stresses for base plate designs with struts, springs, or snubbers with a 5-degrca offset. CYGNA requested TU Electric to address this tolerance in the design calcula-tion. 1.4 Hilti Kwik-Bolt Embedment Length

CYGNA, in pipe support Issue 17, identified a discrepancy between the bc1t's embedment length in the support drawing and the length used in the calculation.

CYGNA has determined that this issue has no impact on the technical aspects of the design. 1.5 Embedded Plate Design l CYGNA, in pipe support Issue 26, identified that in para-graph 3.4 of Appendix 4 of Reference 4.2, Gibbs & Hill requires that all attachments to embedded plates be assumed to be " pin connections" and that moment connections to the embedment require stiffening. Gibbs & Hill did not provide guidelines for the stiffening. The TU Electric pipe support design organization, as noted in l Reference 4.3, assumes that any attachment to the embedded plate will effectively stiffen the local area. This assumption was not validated. 0660BB-1545405-HC4 BB-1

J.O.No. 15454.05-11H 1.6 Potential Concrete Edge Distance Violation CYGNA, as stated in pipe support Issue 31, observed in their Phase 4 pipe support walkdown, that there are instances where pipe sleeve penetrations exist close to support base plates but are not shown on the support drawing. 1.7 Hilti Kwik-Bolts Adjacent to Through-Bolts CYGNA, in pipe support Issue 34, stated that they observed in their walkdown, several instances of Hilti-Kwik bolts installed close to through-bolt base plates that are not shown on the support drawing. 2.0 SWEC's Understanding of the Issue 2.1 Embedment Plates 2.1.1 Pipe support load on embedment plates, attachment location, and attachment spacing must be transmitted to SWEC-CAP for evaluation. l 2.1.2 The embedded plate must be evaluated to verify the assumption of a moment connection. 2.2 Anchor Bolts 2.2.1 Through-bolt loads and base plate loads must be transmitted to SWEC-CAP for wall verification. l 2.2.2 Anchor bolt embedment depth must be accounted for in the support design. 2.2.3 Analysis of base plates must consider the anchor bolt edge distance tolerances. 2.2.4 Anchor Bolt Edge Distance and spacing violations must be documented for evaluation during the pipe support as-built verification effort. 3.0 SWEC's Action Plan to Resolve the Issues 3.1 Ecbedment Plates 3.1.1 Embedded plate qualification is the responsibility of SWEC-CAP in accordance with CPPP-6 and 9, Sec-l tions 7.5.4 and 7.5.1.4, respectively, i 3.1.2 Embedment plate loads are transmitted to SWEC-CAP for l evaluation in accordance with CPPP-6 and 9, Sec-tions 7.5.7 and 7.5.4, respectively. 0660BB-1545405-HC4 BB-2

J.O.No. 15454.05-11H 3.1.3 SWEC-CAP is developing a program to verify that the embedded plate is adequately designed and has sufficient stiffness for the presumption of a moment connection. 3.2 Anchor Bolts 3.2.1 Through-bolt loads and base plate loads are transmit-ted to SWEC-CAP for evaluation in accordance with l CPPP-6 and 9, Sections 7.5.7 and 7.5.4, respectively. 3.2.2 CPPP-7, Revision 3, Attachment 4-4 provides the SWEC procedure for the design of anchor Lolts, including spacing and embedment. . 3.2.3 TU Electric (Reference 4.5) conducted a survey of as-built base plates and determined the maximum edge distances. SWEC performed a study to determine the effects of the increased edge distances on the bolt loads and plate stresses and concluded that the edge distance tolerance has negligible effects on bolt i loads (less than 5 percent increase) and plate stresses (less than 1 percent increase). i 3.2.4 SWEC-CAP must identify all anchor bolt spacing viola-l tions with pipe sleeve penetrations and document them in the as-built program. Spacing violations are evaluated by SWEC in accordance with CPPP-7, -4. 3.2.5 SWEC-CAP is developing a program to identify and doc-I ument in the as-built program anchor bolts located within the cone of influence of through bolts. SWEC will review the results of the program for impact on SWEC scope. 4.0 List of Relevant Documents 4.1 CYGNA Pipe Support Review Issues List, Revision 3, and Trans-mittal Letter No. 84056.106, dated January 9, 1987. 4.2 Gibbs.& Hill Specification No. 2323-MS-46A, Revision 5, Sec-tion 3, Appendix 9, Specification No. 2323-SS-30, Structural Embedments 4.3 L. M. Poppelwell (TU Electric) letter to N. H. Williams (CYGNA) dated April 19, 1984, page 11 l 4.4 N. H. Williams (CYGNA) letter to W. G. Counsil (TU Electric) 5 No. 84056.092 dated October 30, 1985, Pipe Support Review Questions l 0660BB-1545405-HC4 BB-3

J.O.No. 15454.05-11H 9 4.5 TU Electric Engineering Report ER-ME-09 4.6 Civil / Structural Generic Issues

Report, Revision 0, dated November 20, 1986 5.0 Implementation of the Resolution 5.1 A design procedure for anchor bolts is provided in Attach-ment 4-4 of CPPP-7, Revision 3.

5.2 CPPP-6 and 9 control the transmittal of pipe support reaction loads on embedded plates, through-bolts, and base plates to SWEC-CAP (Reference 4.6). l 5.3 The anchor bolt edge distance tolerance has a negligible effect on bolt loads and plate stresses as discussed in Section 3.2.3. 5.4 Spacing violations of anchor bolts with pipe sleeves will be evaluated by SWEC in accordance with CPPP-7, Revision 3, -4. 5.5 SWEC-CAP (Reference 4.6) is developing a program to deal with the interface of anchorage for various commodities. j. 0660BB-1545405-HC4 BB-4

J.0.No. 15454.05-11H REVISION: 1 DATE: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM \\LECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX CC: STRUT / SNUBBER ANGULARITY fk l b D. C. Fostsr R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division f e ;ad-se. C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production v. A. W. Chan Assistant Project Manager - Technical fi.' K C; R. P.,Klause Project Manager l s

J.O.No. 15454.05-11H APPENDIX CC - STRUT / SNUBBER ANGULARITY

1.0 Background

1.1 CASE raised the concern that the loading component that result-ed from the angular swing of the strut / snubber from its nominal position was not assessed. Both CASE and the NRC Staff did agree that a 5-deg tolerance (i 5 deg) is standard industry practice. However, CASE main-tained that the purpose of the tolerance is to prevent the strut / snubber from binding up between the bracket and pin, not to eliminate the loading component from consideration in the support design (Reference 4.1). 1.2 The NRC Staff's position in Reference 4.2 is that the NRC Inspection and Enforcement Bulletin IEB-79-14 program required all as-built angular tolerance over 12 deg to be measured and reported. The construction angular tolerance for the installed CPSES struts / snubbers is 1 5 deg for Unit I and i I deg for Unit 2 (Reference 4.2, see Appendix GG). The CPSES as-built accep-tance criterion is 2 deg for both Units 1 and 2. 2.0 SWEC's Understanding of the Issues 2.1 The effect of the load component that results from the 15-deg swing tolerance of a strut / snubber, due to construction toler-ance and pipe movements, should be considered in support de-sign. If the i 5-deg tolerance is exceeded, the adequacy of the component load rating and paddle binding of the strut / snubber in the clamp and rear bracket should be evaluated. 2.2 The installed struts / snubbers with angular swing exceeding i 2 deg should be documented. 3.0 SWEC's Action Plan to Resolve the Issues 3.1 Angular swing of strut / snubber due to construct. ion tolerance and the pipe movements from the applicable thermal, seismic, and/or fluid transients a're assessed. The effect of the swing angle load component (maximum swing angle of 5 deg) is con-sidered in the support design. If the 1 5 deg tolerance is exceeded, proper function and load rating of strut / snubber as-sembly is ensured in addition to the component load consid-eration. These requirements have been included in rev sed Sections 4.2 and 4.2.6 of CPPP-7 and have been added to the detailed pipe support analysis checklist, Attachment 9-10 of CPPP-6 and Attachment 9-9 of CPPP-9. 0660CC-1545405-HC4 CC-1

J.O.No. 15454.05-11H 3.2 All installed struts / snubbers in Units 1 and 2 that exceeded i 2-deg tolerance are documented by TU Electric in the as-built program. 4.0 List of Relevant Documents 4.1 Transcript of Proceedings of Feedback Discussion Between Walsh and Doyle on the Concerns About the CPSES dated March 23, 1985 4.2 NUREG-0797, Supplementary No. 11, Safety Evaluation Report Re-lated to the Operation of CPSES Units 1 and 2, USNRC, Docket Nos. 50-445 and 50-446, May 1985 5.0 Implementation of the Resolution Sections 4.2 and 4.2.6 of CPPP-7 Revision 3; Attachment 9-10 of CPPP-6, Revision 3; and Attachment 9-9 of CPPP-9, Revision 3, each address this issue. l 0660CC-1545405-HC4 CC-2 mes-- -i-- -

J.O.No. 15454.05-11H Revision: 1 Date: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX DD: COMPONENT QUALIFICATION fkh /5W W N D'. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Maaager - Production A. W. Chan Assistant Project Manager - Technical f/'tha eu R. P. Klausd Project Manager

J.0.No. 15454.05-11H APPENDIX DD - COMPONENT QUALIFICATION

1.0 Background

CYGNA identified five issues related to the qualification of member components in GPSES pipe supports (Reference 4.1) as follows: 1.1 Dynamic Pipe Movements in Support Design CYGNA's concern expressed in Issue 15 of Reference 4.1 was whether all the dynamic piping movements are included in sup-port design when checking frame gaps, swing angles, or spring travel. TU Electric's response (Reference 4.2) addressed the seismic effects only, and other dynamic loads such as water / steam hammer were not mentioned. 1.2 Incorrect Standard Component Al_lowables CYGNA noted in Issue 19 of Reference 4.1 that incorrect U-bolt l allowables were used in the design of support RH-1-064-011-S22R. 1.3 Untightened Locknut On Struts CYGNA noted in Issue 24 of Reference 4.1 that the upper locknut l on one strut was not tightened, which could lead to rotation of the strut and a subsequent load redistribution. 1.4 Inverted Snubbers CYGNA in Issue 25 of Reference 4.1 noted four supports in which the snubbers were installed 180 degrees from the configuration shown on the support drawing. 1.5 Use of A563 Grade A Nuts with High-Strength Bolting CYGNA notes in Issue 28 of Reference 4.1 that ASTM Specifica-tion No. A563 recommends that Grade A nuts be used with the low-strength SA-36 bolting. 2.0 SWEC's Understanding of the Issues 2.1 All static and dynamic piping movements, including the respons-es from seismic events and applicable fluid transients, must be considered in the support design. The movements are as follows: 2.1.1 Frame Gaps in the Unrestrained Direction 2.1.2 Strut and Snubber Swing Angles 2.1.3 Snubber Travel 2.1.4. Spring Travel 0660DD-1545405-HC4 DD-1.

J.O.No. 15454.05-11H 2.2 Standard component-type pipe supports shall be verified or de-signed by comparison to load capacity data sheets (LCDs) or certified design report summaries (CDRS) furnished by the ven-dor unless qualified by unique analyses. 2.3 TU Electric must ensure that locknuts on struts are tightened. 2.4 Inverting the snubber 180 deg from the design drawing has no impact on the component function, stress analysis, or support design. 2.5 The bolts (rod) should be used with nuts of compatible material specified by ASTM. If the materials are not compatible in ac-cordance with ASTM then the load carrying capacity of the bolt / nut assembly should be reviewed for proper load rating. 3.0 SWEC Action Plan to Resolve the Issues 3.1 Dynamic Movements in Support Design 3.1.1 CPPP-7, Section 3.4.5 and Tables 3.5.1 and 3.5.2 specify piping analysis loads and load combinations, including seismic and applicable flow transients. 3.1.2 The pipe stress checklist Attachments 9-9 and 9-8 of CPPP-6 and 9 also address seismic / fluid transient responses. 3.1.3 These loads and movements are available to the sup-port qualification engineer and are combined in ac-cordance with CPPP-7, Table 4.7.2-1. 3.1.4 The pipe support checklist Attachment 9-10 of CPPP-6 and Attachment 9-9 of CPPP-9 address spring travel and strut / snubber movements. 3.1.5 CPPP-7, Revision 3, Section 4.2 specifies that the predicted pipe displacements for all design condi-tions must be considered in the verification / design of component standard-type pipe suppo.rts. 3.2 CPPP-7, Revision 3, Section 4.2 addresses the verification or design of component standard-type pipe supports except for U-bolts as 2-way restraints which are uniquely qualified by analysis in accordance with CPPP-7, Revision 3, -3. 3.3 As recommended by CPRT Action Plan VII.c, the Hardware Valida-tion Program (HVP) (Reference 4.3) will result in a 100-percent reinspection of pipe supports for locking devices and identify necessary rework. 0660DD-1545405-HC4 DD-2

J.0.No. 15454.05-11H^ 3.4 The use of double A563 Grade A nuts with A193 Grade B7 threaded rod for use with Richmond inserts has been evaluated by SWEC and reduced allowables are specified for the nut / bolt combination in CPPP-7, Attachment 4-5.

4.0 List of Relevant Documents 4.1 CYGNA Pipe Support Review Issues List, Revision 3, and Trans-mittal Letter No. 84056.106 dated January 9, 1987 4.2 Communications Report between Wade (TU Electric) and Williams (CYGNA) dated October 4, 1983, Pipe Support Item 3 4.3 TU Electric Hardware Validation Program Revision 3 dated January 7, 1987 5.0 Implementation of the Resolution 5.1 CPPP-6 and 9, -10 and 9-9, respectively, address spring / snubber travel, and strut / snubber angularity.

5.2 CPPP-7, Section 4.2 requires consideration of predicted pipe movement for all design conditions, for component standard-type pipe supports. 5.3 CPPP-7, Revision 3, Section 4.2 requires the verification or design of component standard-type' pipe supports by comparison to vendor-supplied load capacity data sheets (LCD) or certified design report summaries (CDRS) unless qualified by unique anal-ysis such as U-bolts as 2-way restraints (Attachment 4-3). 5.4 CPPP-7, Revision 3, Attachment 4-5 provides reduced allowables for A193 Grade B7 threaded rod when used with A563 Grade A nuts. 0660DD-1545405-HC4 DD-3

J.O.No.,15454.05-11H Revision: 1 Date: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX EE: SSER-8 REVIEW f YI / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. W. Chan Assistant Project Manager - Technical CCu_ - R. P. Klause Project Manager

J.O.No. 15454.05-11H APPENDIX EE - SSER-8 REVIEW

1.0 Background

SSER-8 is the NRC Staff TRT position on the evaluation and resolu-tion of technical concerns and allegations relating to the civil, structural, and miscellaneous issues of CPSES Units 1 and 2. The outstanding issue from SSER-8 that may affect piping support evaluations is TU Electric's action to provide confirmatory evidence that the concrete strength test results substantiate the plant con-crete design strength of 4000 psi. This issue may impact the allow. able loads for anchor bolts. 2.0 SWEC's Understanding of the Issues TU Electric in response to CPRT Action Plan II.b must confirm that in the areas where safety-related concrete was placed between January 1976 and February 1977, the concrete design strength is sub-stantiated by the test program. The capacities of Richmond inserts and anchor bolts are related to their applicable concrete design strength. 3.0 SWEC's Action Plan to Resolve the Issues CPRT Action Plan II,b. " concrete compression strength" (4.2) con-cludes that CPSES safety related concrete placed between January 1976 and February 1977 is substantiated by tests. SWEC has developed allowables for the Richmond inserts and anchor bolts based on a con-crete design strength of 4000 psi. 4.0 List of Relevant Documents 4.1 NUREG-0797, Supplement No. 8, Sections 3.1.3 and 4.1.2, Safety Evaluation Reported Related to the Operation of CPSES Units 1 and 2, USNRC Docket Nos. 50-445 and 50 446, February 1985 4.2 CPRT Action Plan II.b. results report " concrete compression strength" Revision 1 dated February 28, 1986. 5.0 Implementation of the Resolution Allowable loads for Richmond inserts and anchor bolts are based on the CPSES concrete design strength of 4000 psi. These allowables are incorporated into Revision 3 of CPPP-7 as Attachments 4-4, 4-5 and Tables 4.5.5-1, 4.5.6-1, and 4.5.7-1. 0660EE-1545405-HC4 EE-1

J.O.No. 15454.05-11H Revision: 1 Date: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE SUPPORT GENERIC ISSUES REPORT APPENDIX FF: SSER-10 REVIEW / / /Y D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. W. Chan Assistant Project Manager - Technical $hi!c L-R. P. Klause Project Manager

J.O.No. 15 54.05-11H APPENDIX FF - SSER-10 REVIEW

1.0 Background

SSER-10 is the NRC Staff TRT position on the evaluation and resolu-tion of technical concerns and allegations relating to the mechanical and piping group. Four out of the five issues are piping design related. The NRC Staff found these to have potential safety significance and generic implications as follows: 1.1 Uncontrolled Weld Repairs by Plug Welding The NRC requires TU Electric to submit a plan for sampling inspection of plug welds in CPSES for cable tray supports, pipe

supports, and base plates.

TU Electric is to perform a bounding analysis to assess the generic effects of uncontrolled plug welds on pipe supports, cable tray supports, and base plates to serve their intended functions. A report documenting the results of the assessment will be submitted to the NRC Staff. 1.2 Installation of Main Steam Line Pipes - Unit 1, Loop 1 The NRC requires TU Electric to perform Tasks 4.5.1 through 4.5.8 in SSER-10 that include stress assessment and non-destructive examination of Loop 1 main steam (MS) and feedwater l (FW) lines. Results of analysis, examinations, and reviews shall be submitted in a documented report for NRC Staff review. 1.3 Isolation of Seismic Piping from Nonseismic Piping The NRC requires TU Electric to provide analysis and documenta-tion showing that piping systems, such as MS, FW, and auxiliary steam lines routed from seismic Category I to nonseismic Category I buildings meet the FSAR criteria. 1.4 As-Built Verification of Type 2 Skewed Welds on NF Supports The NRC requires TU Electric to confirm, 'either by verifying previous inspections or by reinspection, that the Type 2 skewed welds on pipe supports are not undersized. 2.0 SWEC's Understanding of the Issue 2.1 The effects of undocumented and uninspected plug weld repairs in some critical-area support members need to be evaluated. A sampling inspection and/or bounding analysis of the plug welds for pipe supports, cable tray supports, and baseplates is needed. 2.2 As reported in Reference 4.2, Section 6.0, the sequence of events associated with the main steam line lifts was determined 0660FF-1545405-HC4 FF-1

J.O.No. 15454.05-11H to differ in certain aspects from the sequence implied by the TRT. Existing documentation supplemented by interviews estab-lished a sequence described in Reference 4.2 and was evaluated. Main steam and feedwater piping stress analyses, incorporating bounding parameters, provide an adequate basis for concluding that there were no deleterious effects resulting from the se-quence of events. 2.3 Piping routed from the seismic safeguards building to the non-seismic turbine building must be isolated from the effects of nonseismic piping and the nouseismic turbine building. The anchors or restraints used for isolation purposes must be de-- signed to withstand the combined loading imposed by both the seismic and nonseismic piping. 2.4 The lack of inspection criteria and procedures on Type 2 skewed welds could lead to undersized welds. Documented inspection results of Type 2 skewed welds on NF supports are necessary to ensure its intended function. 3.0 SWEC's Action Plan to Resolve the Issues 3.1 As concluded by Reference 4.3, undocumented plug welds not re-inspected under the ISAP action plan will not compromise the structural integrity of the components. Therefore, no further action is required. 3.2 As concluded by Reference 4.2, no deleterious effects resulted from the sequence of events associated with Unit 1 Main Steam Loop and Hydro. Therefore, no further action is required. 3.3 The design procedure of interface anchors used for isolation purposes is contained in Attachment 4-10 of CPPP-7. SWEC as part of the piping system review discussed in CPPP-6 and 9 re-views all piping stress problems within their scope to assure proper isolation from non seismic piping systems and/or struc-tures. Stress boundaries are redefined and isolation anchors added as required. 3.4 This issue is being addressed by TU Electric's CPRT Action Plan V.a addressing NRC TRT issue V.a. SWEC will review upon issue the CPRT results report on this topic and assess the impact if any on SWEC's work scope. ~ 4.0 List of Relevant Documents 4.1 NUREG-0797, Supplement No. 10, Safety Evaluation Report related to the operation of CPSES Units 1 and 2, USNRC Docket Nos. 50-445 and 50-446, April 1985 4.2 CPRT Results Report ISAP - V.e, Installation of Main Steam Pipes, Revision 2, dated October 15, 1986. 0660FF-1545405-HC4 FF-2

J.O.No. 15456.05-11H 4.3 CPRT Re'sults Report ISAP-V.d, Plug Welds, Revision 1, dated December 18, 1986. 5.0 Implementation of the Resolution 5.1 SWEC has reviewed the CPRT Action Plan V.d results report (Reference 4.3) and has concluded that there is no impact on the requalification of pipe supports at CPSES. 5.2 SWEC has reviewed the CPRT Action Plan V.e results report 1 (Reference 4.2) and has concluded that this event has no impact on the requalification of pipe stress and pipe supports at CPSES. 5.3 The design procedure for interface anchors is contained in -10 of CPPP-7. 5.4 SWEC will review the CPRT Action Plan V.a results report upon l issue for impact on pipe supports at CPSES. 0660FF-1545405-HC4 FF-3

R-J.O.No. 15454.05-11H Revision: 1 Date: 07/24/87 TU ELECTRIC COMANCHE PEAK STEAM ELECTRIC STATION STONE & WEBSTER ENGINEERING CORPORATION'S LARGE BORE PIPE STRESS AND PIPE EUPPORT GENERIC ISSUES REPORT APPENDIX GG: SSER-11 REVIEW ff / D. C. Foster R. R. Wrucke Chief Engineer Project Engineer - Unit 1 Engineering Mechanics Division C. A. Fonseca Project Engineer - Unit 2 Assistant Project Manager - Production A. W. Chan Assistant Project Manager - Technical Ib 4'a' s R. P. Klause Project Manager

J.O.No. 15454.05-11H APPENDIX GG - SSER-11 REVIEW

1.0 Background

/.j SSER-11 is the NRC Staff TRT position on the evaluation and resolu-tion of technical concerns and allegations relating to the QA/QC Group. The concerns or deficiencies identified by SSER-11 in the design process that are related to piping design are as follows: 1.1 As-Built Inspection Program (Allegations AQ-50, AQ-21, AQ-22, and AQ-119, Reference 4.1) The NRC Staff classified the as-built concern into hardware, procedure, as-built, and weld-related problems. Specifically, the NRC Staff listed six generic pipe support construction deficiencies in Unit I as follows: 1.1.1 Excessive snubber spherical bearing clearance 1.1.2 Strut and snubber load pin locking device missing. 1.1.3 Pipe clamp halves not parallel. 1.1.4 Snubber adapter plate bolts not fully engaged. 1.1.5 Hilti-Kwik bolts installed with less than minimum embedment. 1.1.6 Absence of locking devices for threaded fasteners on NF supports. 1.2 Design Engineering did not always use isolation anchors in the design of seismic-to-nonseismic piping. The isolation anchor must be designed to withstand the combined loading imposed by both seismic Category I and nonseismic Category I piping. (Al-legation SRT-13, Reference 4.2). 1.3 The design of the main steam lines in Unit 1 did not take into account the strecses caused by repositioning the line after flushing and by the settling of temporary supports. (Allega-tion AP13, Ref. 4.2) 1.4 Inadequate analysis consideration pertaining to radial shrink-age of girth welds in thin-walled stainless steel pipe. (Alle-gations AQ-50, Ref. 4.1; and AW-52, AW-59, AW-62, Ref. 4.2) 2.0 SWEC's Understanding of the Issue 2.1 As-built QC verification is needed on the adequacy ~ of CPSES pipe support members to meet the specifications for their in-tended function. 0660GG-1545405-HC4 GG-1

J.O.No. 15454.05-11H 2.2 Design of the isolation anchors between seismic and nonseismic piping must be addressed. This topic was also identified in SSER-10 and is discussed in Appendix FF. No further discussion will be provided in this appendix. 2.3 The Unit 1 main steam loop hydro concerns were also identified in SSER-10 and are discussed in Appendix FF. No further dis-cussion will be provided in this appendix. 2.4 A procedure to analyze the radial shrinkage of girth welds is needed. 3.0 SWEC's Action Plan to Resolve the Issues 3.1 The six attributes listed in Section 1.1 will be reinspected by Brown and Root QC in the Hardware Validation Program (Refer-ence 4.3), modifications will be identified, and the required rework will be performed. 3.2 A procedure to analyze the effect of radial shrinkage and qual-ification of girth welds has been incorporated in CPPP-7, Revision 3, as Attachment 3-15. 4.0 List of Relevant Documents 4.1 NUREG-0797, Supplement No. 11, Safety Evaluation Report related to the operation of CPSES Units 1 and 2, USNRC Docket Nos. 50-445 and 50-446, May 1985 4.2 NUREG-0797, Supplement No. 10, Safety Evaluation Report related to the operation of CPSES Units 1 and 2, USNRC Docket Nos. 50-445 and 50-446, April 1985 4.3 TU Electric Hardware Validation Program, Revision 3, Janu-ary 7, 1987. 5.0 Implementation of the Resolution 5.1 A procedure to analyze and qualify the girth welds has been incorporated into CPPP-7, Revision 3 as Attachment 3-15. 0660GG-1545405-HC4 GG-2 ,-m m-mi-men.imum-sm--m-eem}}

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