ML18033A184

Forwards Rev 1 to Civil Engineering Branch Instructions CEB-CI 21.97, Operability Criteria for Pipe... & Program for Resolving Small Bore Piping Issue,Per 880318 Meeting W/ NRC to Resolve IE Bulletins 79-02 & 79-14

ML18033A184
Person / Time
Site:	Browns Ferry
Issue date:	04/29/1988
From:	Gridley R TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
Shared Package
ML18033A186	List: ML18033A184 ML18033A188
References
IEB-79-02, IEB-79-14, IEB-79-2, TAC-00016, TAC-00020, TAC-00305, TAC-16, TAC-20, TAC-305, NUDOCS 8805040413
Download: ML18033A184 (12)

Text

t. REGULATQt INFORMATION DISTRIBUTION 'EM (RIDS)

ACCESSION NHR:8805040413 DQC. DATE: 88/04/29 NOTARIZED: NQ DOCKET FACIL: 50-260 BroUJns Ferry Nuclear Poeer Stations Unit 2I Tennessee 05000260

'UTH. NAME . AUTHOR AFFILIATION GRIDLEYi R. Tennessee Valley Authority REC IP. NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Forwards Rev 1 to Civil Engineering Branch Instructions CEB-CI 21. 97'Operability Cri teria For Pipe... " 5 program For resolving small bore piping issuei per 880318 meeting e/

NRC to resolve IE Bulletins 79-02 5 79-14.

DISTRIBUTION CODE: DOSDD COPIES RECEIVED: LTR i ENCL J SIZE: +

TITLE: TVA Facilities Routine Correspondence NOTES: G. Zech 3 cg. 1 cg. ea to: Ebneteri Axelradi S. Richardsoni 05000260 B. D. Liaei K. Hart I QI.

RECIPlENT COPIES REC IP IENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL JAMERSONi C 1 1 PD 1 1 MORAN' 1 1 GEARS' 1 1 INTERNAL: ACRS 1 1 *DM/LFMB 1 0 A 1 1 OGC 15-B-18 0 EG FI 01 EXTERNAL: LPDR NRC PDR NSIC 1 1 NOTES:

TOTAL NUMBER OF COPIES REQUIRED: LTTR 21 ENCL 19

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TENNESSEE VALLEY AUTHOR1TY CHATTANOOGA. TENNESSEE 37401 5N 157B Lookout Place APR 89 1~88 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Hashington, D.C. 20555 Gentlemen:

In the Matter of 'ocket,Nos. 50-260 Tennessee Valley Authority BROHNS FERRY NUCLEAR PLANT (BFN) SEISMIC QUALIFICATION OF SMALL BORE PIPING, CONTROL ROD DRIVE INSERT AND NITHDRANAL PIPING, AND IE BULLETINS 79-02 AND 79-14 (NRC TAC NOS. 00305, 00020 AND 00016)

This letter describes the BFN program for the seismic qualification of small bore piping and pipe supports. This material was requested by R. J. Clark's letter dated July, 1986 to S. A. White. This letter supplements the information provided by R. Gridley's letters dated April 8, 1987 and March 10, 1988 and section III.3.7 of revision 1 to the BFN Performance Plan that was transmitted by S. A. Nhite's letter dated July 1, 1987. This letter incorporates resolution of the NRC staff's concerns as discussed in our meeting, dated March 18, 1988. to this letter describes the BFN program for resolving the small bore piping issue, Enclosure 2 provides the BFN interim operability criteria for pipe and pipe supports on TVA Class I seismic piping, revision 1. These criteria are also being utilized on the program to seismically qualify control rod insert and withdrawal piping and in the program to resolve IE Bulletins 79-02 and 79-14. TVA requests your review of this program and the issuance of a written statement documenting the program's acceptability.

Please refer any questions regarding this submittal to M. J. May, Manager, BFN Site Licensing, (205) 729-3570.

Very truly yours, TENNESSEE VALLEY AUTHORITY R. Gri ey, Director Nuclear Licensing and Regulatory Affairs Enclosures cc: See page 2 gpss 8805040413 PDR ADOCN; 0500>~DR i/I 8

An Equal Opportunity Employer

0 'I U.S. Nuclear Regulatory Commission cc (Enclosures):

Mr. K. P. Barr, Acting Assistant Director for Inspection Programs TVA Projects Division U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 Mr. G. G. Zech, Assistant Director for Projects TVA Projects Division U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockvi lie, Maryland 20852 Browns Ferry Resident Inspector Browns Ferry Nuclear Plant Route 12, P.O. Box 637 Athens, Alabama 35611

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ENCLOSURE 1 TENNESSEE VALLEY AUTHORITY BROWNS FERRY. NUCLEAR PLANT UNIT 2 SMALL BORE PIPING AND SUPPORTS MARCH 1988 This report provides TVA's plan for specific acti. on to qualify seismic Class I field run small bore piping.

Issue Significant condition reports have questioned the adequacy of base plates, concrete anchors, weld details, and structural integrity of supports for safety-related small bore pi.pi.ng. These questions revolve around the criteria used to design and install those supports.

Back round The majority of the Class I small bore (one-half to two-inch diameter) piping at Browns Ferry Nuclear Plant (BFN) was field routed and field supported.

Installation was in accordance with American National Standards Institute standards. Two criteria were issued for BFN small bore piping design. The first design criteria was "Design Criteria for Supporting Process Instrument Piping and Instrument Air Lines," dated May 3, 1971. The other was "Criteria for Seismically Qualifying Field Run Piping Sizes 1/2 through 2 in.," which was issued on November 29, 1972. Both criteria were reissued as controlled document BFN-50-712 in 1972.

In 1984, a nonconformance report (NCR BFNMEB 8406) was written on the application of BFN 50-712 to the installation of schedule 160 pipe since the schedule 160 pipe was not addressed in this design cri.teria. Mhile revising BFN 50-712 to address schedule 160 pipe, it was determined that the qualification of some base plates in the typical support details of the criteria could not be verified and that no weld details had been specified. It was also determined that some support members for field-routed schedule 160 piping could be underdesigned since their selection was based on the tables in the design criteria for schedule 40 and 80 piping. A significant condition report (SCR BFNCEB 8520) was written addressing those conditions and BFN 50-712 was revised to place the support details on hold pending the resolution of the SCR.

Resolution The scope of this activity for unit 2 and the required common small bore piping is estimated to be 16,000 ft. of pipe with 750 supporting structures. The following types of piping are excluded from this evaluation:

a) Piping reviewed under the long-tenn torus integrity program b) Piping reviewed under 79-14 program c) Control Rod Drive piping

In order to address the concerns reg'arding the seismic qualification of Class I small bore piping, representative piping problems (approximately 10 percent of the total scope) were selected for evaluation. The following attributes were considered:

High temperature/high pressure systems Large concentrated weights (i.e., valves)

Large differential movements (i.e., source pipe connections)

Seismic non-seismic overlap Schedule 160 piping Plant. location Different pipe sizes This evaluation will consist 'of walkdowns of the selected piping, evaluation of this data to design cri:teria requirements and review to the operabili.ty criteri.a to determine required modificati.ons. Those piping and supports which do not meet the design criteria, but are within the interim operability criteria, will be modified to the design criteria after restart. Those which do not meet the interim operability criteria will be modified to the design criteria unless specifically requested and approved, by NRC on a ease-by-ease basis prior to restart. A comparison of design and operabi.lity criteria is summarized in table 1.

Attributes will be identifi.ed for those supports which require modifications to meet the operability criteria. These attributes will then be reviewed for generic implications,to the entire small bore scope. The representative scope will be increased as determined necessary by an extensive root cause analysis and evaluation of the extent-of-condition. This review will address the interdependency of discrepancies and the impact due to the general accumulation of discrepancies.

The design criteria for small bore piping and supports satisfy the FSAR.

Specific requirements for piping and supports are provided in Appendix C of the FSAR.

Licensin'ssues I "sue:

This program involves the use of interim operability criteria for piping and supports.

Just,ification:

These criteria, as documented in CEB-CI 21.97, assure structural integrity of the piping and supports and are used for the 79-14 program. The criteria are similar to those approved on Sequoyah Nuclear Plant for large bore supports.

Approval of the Sequoyah operability criteria is documented in NUREG 1232. For a comparison between Sequoyah's and Drowns Ferry's operability criteria, refer to table 2.

The small bore qualification program is. comprehensive and provides assurance that piping and supports will remain functional. Modifications required to meet design criteria will be implemented prior to start-up after the next refueling outage.

ENCLOSURE 1 TABLE 1 BROWNS FERRY UNIT 2 SMALL BORE PIPING CRITERIA COMPARISON CHART COMPONENT DESIGN CRITERIA OPERABILITY CRITERIA PIPING PRINARY 1.8SH 2SY SECONDARY SA ASME Eg 10 PRIMARY 6 SECONDARY SA + SH ASME EQ 11 OR AUGMENTED FATIGUE EVALUATION CONCRETE WEDGE TYPE 4 ALL TYPES EXPANSION ANCHORS SHELL TYPE 2 FACTOR OF SAFETY 5 FOR TENSION WEDGE AND SHELL 4 FOR SHEAR PIPE SUPPORT 1.5 X AISC LESSER OF 0'7SU OR TENSILE AND FLEXURAL MAXIMUM LIMIT 0.9SY 1.2SY STRESS COMPRESSIVE STRESS 1.5X AISC MAXIMUM LIMIT 0.9PCR MAXIMUM LIMIT 0.9SY ALLOWABLE SHEAR MAXIMUM LIMIT LESSER OF 0.42SU OR STRESS 0.52SY 0.72SY STRESS BOLT 0.56SU SY ~MIN) (WHEN NOT AVAILABLE '7SU)

ENCLOSURE 1 TABLE 2 BROWNS FERRY UNIT 2 SMALL BORE PIPING COMPARISON OF OPERABILITY CRITERIA TECHNICAL ATTRIBUTES SEQUOYAH BROWNS FERRY COMPONENT CEB-CI-12-89 CEB-CI-21-97

~Pi in PRIMARY 2SY 2SY lo ASME EQ 10 SECONDARY PRIMARY & SECONDARY ASME EQ ASME EQ 11 OR AUGMENTED FATIGUE ASME EQ ll OR AUGMENTED FATIGUE EVALUATION EVALUATION STRAINS CODE CASE N-47 WILL NOT USE APPEND T LIMITS CONCRETE EXPANSION ANCHORS ALL TYPES ALL TYPES FACTOR OF SAFETY 2 2 PIPE SUPPORT LESSER OF 1.2SY LESSER OF 1.2SY TENSII E AND FLEXURAL & .7SU & .7SV STRESS COMPRESSIVE STRESS MAXIMUM LIMIT MAXIMUM LIMIT OF .9PCR OF .9PCR SHEAR STRESS LESSER OF .42SU LESSER OF 0.42SU

& .72SY & .72SY STRESS BOLT SY SY OR .7SU WHEN SY (MINi IS NOT SPECIFIED LOAD SHARING BY USE ON CASE BY CASE USE ON CASE BY CASE ADJACENT SUPPORTS BASIS BASIS THERMAL MONITORING USE AS METHOD OF USE AS METHOD OF DEFERRING MODIFICATION DEFERRING MODIFICATION