ML17331B385

LER 94-004-00:on 940406,three Pressurizer Safety Valves Sent to Offsite Test Lab for Testing for Failure to Meet TS Acceptance Criteria.Cause Not Determined.Nozzle & Disc Seating Surfaces Lapped & polished.W/940510 Ltr

ML17331B385
Person / Time
Site:	Cook
Issue date:	05/10/1994
From:	Blind A, Weber G INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-94-004, LER-94-4, NUDOCS 9405190369
Download: ML17331B385 (6)

Text

ACCELERATED ITRIBUTION DEMONS'ATION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)ACCESSION NBR:9405190369 DOC.DATE: 94/05/10 NOTARIZED:

NO DOCKET g FACIL:50-315 Donald C.Cook Nuclear Power Plant, Unit 1, Indiana M 05000315 AUTH.NAME AUTHOR AFFILIATION WEBER,G.A.

Indiana Michigan Power Co.(formerly Indiana&Michigan Ele BLIND,A.A.

Indiana Michigan Power Co.(formerly Indiana&Michigan Ele RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 94-004-00:on 940406,three pressurizer safety valves, sent to to off site test lab for testing failed to meet TS acceptance criteria.Cause not determined.

Nozzle&disc seating surfaces lapped&polished.W/940510 ltr.DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR (ENCL 0 SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.NOTES: RECIPIENT ID CODE/NAME PD3-1 PD INTERNAL: AEOD/DOA AEOD/ROAB/DS P NRR/DE/EMEB NRR/DRCH/HHFB NRR/DRCH/HOLB NRR/DRSS/PRPB NRR/DSSA/SRXB RES/DSIR/EIB EXTERNAL: EG&G BRYCE,J.H NRC PDR NSIC POORE,W.COPIES LTTR ENCL 1 1 1 1 2 2 1 1 1 1 1 1 2 2 1 1 1 1 2 2'1 1 1 1 RECIPIENT ID CODE/NAME HICKMAN,J AEOD/DSP/TPAB NRR/DE/EELB NRR/DORS/OEAB NRR/DRCH/H I CB NRR/DRI L/RPEB NRR DSSA/SPLB GREG 02 FILE 01 L ST LOBBY WARD NSIC MURPHY,G.A NUDOCS FULL TXT COPIES LTTR ENCL 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 NOTE TO ALL"RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE iVASTE!CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT.20079)TO ELIMINATE YOUR NAME FROiVi DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED'TTR 27 ENCL 27 Indiana Michig Power Company Cook Nuclear Plant One Cook Place Bridgrnan, Ml 49106 616 465 5901 INDlANA NICHlGi4N POWE'R May 10, 1994 United States Nuclear Regulatory Commission Document Control Desk Rockville, Maryland 20852 Operating Licenses DPR-58 Docket No.50-315 Document Control Manager: In accordance with the criteria established by 10 CFR 50.73 entitled Licensee Event Re ort S stem the following report is being submitted:

94-004-00 A.A.Blind Plant Manager/sb Attachment c'.B.Martin, Region III E.E.Fitzpatrick P.A.Barrett R.F.Kroeger M.A.Bailey-Ft.Wayne NRC Resident Inspector J.B.Hickman-NRC J.R.Padgett G.Charnoff, Esq.D.Hahn INPO S.J.Brewer q n.~, i~U l,s<I'-v'7405190369 940510 PDR ADOCK 05000315 S PDR NRC FORM 366 (5 92)U.S.NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO.3150.0104 EXP IR ES 5/31/95 LICENSEE EVENT REPORT (LER)(See reverse for required number of digits/characters for each block)ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMADON COLLECTION REQUEST: 50.0 HRS.FORWARD COMMENTS REGARDUIG BURDEN ESDMATE TO THE INFQRMATICN AND RECORDS MANAGEMENT BRANCH (MNBB Tr ta), U.S.NUCLEAR REGULATORY COMMISSION>

WASHINGTON, DC 20555 0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150010a), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503, FACILITY NAME (I)D.C.COOK NUCLEAR PLANT-UNIT 1 DOCKET NUMBER (2)05000 315 PAGE P)10F 3 FAILURE OF THREE PRESSURIZER SAFETY VALVES TO'MEET TECHNICAL SPECIFICATION RVEILLANCE TEST CRITERIA EVENT DATE 5 LER NUMBER 6 REPORT NUMBER 7 OTHER FACILITIES INVOLVED 6 MONTH 04 DAY 06 YEAR 94 YEAR 94 SEQUENTIAL NUMBER 004 REVISION NUMBER 0 MONTH DAY 05 10 94 FACIUTY NAME FACILITY NAME DOCKET NUMBER 05000 DOCKET NUMBcR 05000 OPERATING MODE (9)20A02(b)20.405(c)50.73(a)(2)(iv)73.71(b)NT TO THE REQUIREMENTS OF 10 CFR E: Check one or m THIS REPORT IS SUBMITTED PURSUA ore 11 POWER LEVEL (10)0 20.405(a)(1)(i)20.405(a)(1)(ii)20.405(a)(1)(iii)20.405(a)(1)(iv)2o.405(a)(1)(v) 50.36(c)(1)50.36(c)(2)X 50.73(a)(2)(i) 50.73(a)(2)(ii)50.73(a)(2)(iii)LICENSEE CONTACT FOR THIS LER 12 M73(a)(2)(v) 50.73(a)(2)(vii)50.73(a)(2)(viii)(A)50.73(a)(2)(viii)(B) 50.73(a)(2)(x) 73.71(c)OTHER (Speoty in Atrctract tretow and in Text, NRC Form 366A)NAME G.A.WEBER-PLANT ENGINEERING SUPERINTENDENT TELEPHONE NUMBER Fnctvde Area code)(616)465-5902 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 13 CAUSE SYSTEM COMPONENT RV MANUFACTURER C710 REPORTABLE TO NPRDS , D.;j.x',~CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO NPRDS SUPPLEMENTAL REPORT EXPECTED 14 YES 0(yee, cornptete ExPEGTED sUBMIssIQN DATE)NO ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single.spaced typewritten lines)(16)EXPFCTFD MONTH DAY YEAR SUBMISSION DATE (15)On Apri.l 6, 1994 with Uni.t 1 in Mode 5 (Cold Shutdown)it was determined that all three of the pressurizer safety valves, which were sent to an off site test laboratory for testing, were found with lift settings outside of the Technical Specification acceptance criteria.Acceptable settings are between, 2461 psig and 2509 psig.Valve 1-SV-45A was found to have a lift setpoint of 2536 psig, valve 1-SV-45B had a lift setpoint of 2535 psig and 1-SV-45C had a lift setpoint of 2538 psig.There was no safety-signi.ficance since the worst case (1-SV-45C-lift setpoint of 2538 psig)would result in a maximum transient pressure of 2615 psig (2538 psig plus 3 percent accumulation to attain its full rated lift).This is below the Technical Specification safety limit of 2735 psig.All three valves were partially disassembled (retaining spring compression) and inspected.

No problems were noted.The nozzle and disc seating surfaces were lapped and polished.The valves were reassembled and tested satisfactori.ly.

The safety valve conditions experienced at the D.C.Cook Plant are similar to current i.ndustry trends/concerns.

-Since a specific Root Cause could not be determined, no preventive action i.s planned at this time.However, we will be evaluating the test methods and industry activities pertaining to the pressurizer safety valves.NRC FORM 366 (5-92)

REQUIRED NUMBER OF DIGITS/CHARACTERS FOR EACH BLOCK BLOCK NUMBER NUMBER OF DIGITS/CHARACTERS UP TO 46 8 TOTAL 3 IN ADDITION TO 05000 VARIES TITLE FACILITY NAME DOCKET NUMBER PAGE NUMBER 10 12 13 14 15 UP TO 76 6 TOTAL 2 PER BLOCK 7 TOTAL 2 FOR YEAR 3 FOR SEQUENTIAL NUMBER 2 FOR REVISION NUMBER 6 TOTAL 2 PER BLOCK UP TO 18*.FACILITY NAME 8 TOTAL-DOCKET NUMBER 3 IN ADDITION TO 05000 1 CHECK BOX THAT APPLIES UP TO 50 FOR NAME 14 FOR TELEPHONE CAUSE VARIES 2 FOR SYSTEM 4 FOR COMPONENT 4 FOR MANUFACTURER NPRDS VARIES 1 CHECK BOX THAT APPLIES 6 TOTAL 2 PER BLOCK TITLE EVENT DATE LER NUMBER REPORT DATE OTHER FACILITIES INVOLVED OPERATING MODE POWER LEVEL REQUIREMENTS OF 10 CFR LICENSEE CONTACT EACH COMPONENT FAILURE SUPPLEMENTAL REPORT EXPECTED EXPECTED SUBMISSION DATE NRC FORM 366A r (669)U.S.NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)TEXT CONTINUATION APPROVED OMB NO.31500104 EXPIRES: 4/30I92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REOUESTI 50.0 HRS.FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH (F630), U.S.NUCLEAR REGULATORY COMMISSION, WASHINGTON, OC 20555, AND TO 1HE PAPERWORK REDUCTION PRO)ECT (31500104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.FACILITY NAME (1)DOCKE'T NUMBER (2)LER NUMBER (6)PAGE (3)YEAR Hr5 SEOUENTIAL NUMBER REVISION NUMSFR D.C.COOK NUCLEAR PLANT-UNIT 1 TEXT (if more 4Pece Je eetrr9ed, Iree eddttr'one)

NRC Forrrr 3IJSA'et (12)o 5 o o o 315 94 0 0 4-0 0 0 2 OF 0 3 Conditions Prior to Occurrence:

Unit One-Mode 5 (Cold Shutdown-following refueling).

Descri tion of Event: On April 6, 1994, it was determined that all three safety pressurizer safety valves, Crosby Valve Model HB-86-PB, (EZIS/AB-RV) had lift settings outside Technical Specification 3.4.3 acceptance criteria.The safety valves are tested at a test laboratory using steam at nominal temperature and pressure, as required by Technical Specification.

The valves are required to lift at 2485 psig plus or minus 1 percent, (i.e.between 2461 and 2509 psig).Valve 1-SV-45A was found to have a lift setpoint of 2536 psig, valve 1-SV-45B had a lift setpoint of 2535 psig and 1-SV-45C had a lift setpoint of 2538 psig.Technical Specification 4.4:3 requires that each Pressurizer Code Safety Valve be demonstrated operable per Section XI of the ASME Boiler and Pressure Vessel Code, 1974 Edition.Cause of Event: The safety valve conditions experienced at the D.C.Cook Plant are similar to current industry trends/concerns.

The phenomenon of safety valve setpoint drift outside of design tolerances is common in the Nuclear industry.However, as yet, no cause for the drift has been determined.

1-SV-45A, 1-SV-45B and 1-SV-45C were partially disassembled (retaining spring compression) and inspected.

No problems were noted.The nozzle and disc seating surfaces were lapped and polished.The valves were reassembled and tested satisfactorily.

The test program (test facility and procedure) for the Pressurizer Safety Valves has not changed from previous testing.Anal sis of Event: This event has been determined to be reportable under the provisions of 10CFR5073(a)(2)(i)(B) as an operation prohibited by Plant Technical Specification 3.4.3, which requires all of the pressurizer safety valves to be operable with a lift setting of 2485 psig+/-1 percent.The as-found lift setpoints of safety valves 1-SV-45A, 1-SV-45B and 1-SV-45C did not have any actual impact on the Reactor Coolant System (RCS)since the safety valves were not challenged during the last fuel cycle.There was no potential impact since the RCS would not have exceeded the maximum transient limit of 2735 psig, which is 110 percent of design pressure (2485 psig).There was no impact on the health or safety of the public.Safety Valve 1-SV-45C (worst case)had a lift setpoint of 2538 psig.The RCS pressure would have to reach a pressure of 2615 psig (2538 psig plus 3 percent accumulation) for this valve to attain its full rated lift.Valve 1-SV-45A would have attained its rated lift at 2612 psig (2536 psig plus 3 percent)and 1-SV-45B would have attained its rated lift at 2612 psig (2535 plus 3 percent).NRC Form 366A (669)

NRC FORM 366A (64)9)U.S.NUCLEAR REGULATORY COMMISSIO LICENSEE EVENT REPORT (LER)TEXT CONTINUATION APPROVED OMB NO.31504))04 EXPIRES)4/30/92 ESTIMATED BURDEN PER RESPONSE TO COMPLY WTH THIS INFORMATION COLLECTION REGUESTI 500 HRS.FORWARD COMMENTS REGARDING BUADEN ESTIMATE TO THE RECORDS AND REPORTS MANAGEMENT BRANCH IP430), U.S.NUCLEAR AEGULATOAY COMMISSION, WASHINGTON, OC 20555, AND TO THE PAPERWORK REDUCTION PAOJECT (31500104), OFFICE OF MANAGF MENT AND BUDGET, WASHINGTON, OC 20503.FACILITY NAME (1)DOCKET NUMBER (21 LFR NUMBER (6)PAGE (3)YEAR)'.yi(SSOVSNTIAL NVMSSR REVISION NVM 54 D.C.COOK NUCLEAR PLANT-UNIT 1 TEXT///mttt tptct B nqvnd.IItt tddldoIM//Y/IC Fdmt 3/)BA'4/(I 2)0 5 0 0 0 3 I 5 9 4 0 0 4 00 03 oF 0 Anal sis of Event continued!

The reactor vessel and pressurizer were designed to ASME BGPV Section III which permits a maximum transient.

pressure of 2735 psig, 110 percent of design pressure (2485 psig).The RCS piping, valves and fittings are designed to ANSI B31.1, 1967 Edition, which permits a maximum transient pressure of 2985 psig, 120 percent of design pressure (2485 psig).In addition, the entire RCS was hydro tested to 3107 psig, 125 percent of design (2485 psig), to demonstrate system integrity prior to initial operation.

In conclusion, this event did not have any safety significance and did not represent a hazard to the public health and safety.The safety limit of 2735 psig would not have been exceeded since the maximum RCS pressure would not have exceed 2615 psig (1-SV-45C setpoint of 2538 psig plus 3 percent).In addition to this Safety Analysis, an additional Safety Evaluation is being performed to review the combined effect of recent Main Steam Safety Valve lift setpoints (reported in LER 50-315/94-001 and 94-003)in conjunction with the as-found lift setpoints of the Pressurizer Safety Valves.This evaluation is scheduled to be completed by June 30, 1994.We do not anticipate any adverse conditions to be identified during this evaluation, however, an updated LER will be submitted if deemed necessary.

Corrective Action: The nozzle and disc seating surfaces were lapped and polished for all three safety valves.Retests were satisfactorily completed for steam set pressure and seat leakage.The spring pressure on 1-SV-45A was adjusted by 1/3 flat to bring the set pressure back into tolerance.

Since a specific Root Cause could not be determined, no preventive action is planned at this time.However, we will continue to follow industry activities pertaining to safety valve setpoint drift.Failed Com onent Identification:

Pressurizer Safety Valve Plant Designation:

1-SV-45A, 1-SV-45B and 1-SV-45C Manufacturer:

Crosby Valve Company Model: HB-86-BP EIIS Code: AB-RV Previous Similar Events: LERS 50-315/90-16, 92-09 LER: 50-316/89-04, 92-06 NRC Form 366A (669)