ML20090D290

Preliminary AO 50-219/75-16:on 750614,electromatic Relief Valve Pressure Switches 1A83B & E Tripped at Pressure Exceeding Tech Spec Limit.Caused by Instrument Setpoint Drift.Switches Reset

ML20090D290
Person / Time
Site:	Oyster Creek
Issue date:	06/16/1975
From:	Carroll J JERSEY CENTRAL POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
AO-50-219-75-16, NUDOCS 8302250479
Download: ML20090D290 (4)

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c . ,97 TO: Jaocs P. O'Itcilly ,l.'1 Directorate of Regulatory Operations L'" 77;.7

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Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 FROM: Jersey Centra! . Power G Light Company

. Oyster Creek Nuclear Generating. Station Docket l'50-21 Forked River, New Jersey OS731 w

SUBJECT:

Abnormal Occurrence Report No. 50-219/75/ 16 The fellowing is a prelirainary report being subraitted in cor:pliance with the Technical Specifications, paragraph 6.6.2.

Prelirtinary Approval:

. /.Y 8302250479 750616

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PDR ADOCK 05000219 4' -

S PDR J. T. Carrolli,{Jr. Date CC: Mr. A. Giambusso Y m % t7 34 O!vy

initial Tele,phope Date of acport Late: 6/ , 'S -

Occurrf')\c:

6/14/75 Initia* Written Time of

^6/16/75 Occurrence: 0200 ucport. Date:

OYSTER CREEK NUCLEAR GENERATING. STATION . _. ..

f0RKED RIVER, NEW JERSEY 08731 ,

Abnonnal Occurrence Report No. 50-219/75/16 IDENTIFICATION Violaticn of the Technical Specifications, paragraph 2.3.4, 3F OCCURRENCE:

Electroinatic Relief Valve Pressure Switches, IA33B and 1AS3E, were found to trip at pressures. in excess of the maximum allowable value of 1070 psig.

This event is considered to be an abnormal occurrence as de-

. fined in the Technical Specifications, paragraph 1.15A.

CONDITICSS PRIOR Steady ,S,t, ate Power _ Routine Shutdown TO OCCURRENCE: I!ot Standby Operation Cold Shutdown Load Changes During Refueling Shutdown Routine Power Operation' Routine Startup X ,,0ther (Specify)

Operation The reactor mode switch was in the REFUEL position with 0

reactor coolant temperature less than 212 F.

DESCRIPTION OF - On Saturday, June 14, 1975, while performing surveillance on the OCCURRENCE:

five !!1cetromatic Relief Valve Pressure Switches, it was found that 1A83B and 1A83E tripped at 1089 psig and 1085 psig,

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respectively. These values arc in excess of the maximum allowabic trip points of 10S4 psig and 1082 psig, respectively, which are derived by adding appropriate head correction factors to the Technical Specification limit of 1070 psig.

It is noted here that switches 1AS5B and 1AS3E are associated with valves NR108B and NR10811, respectively.

Abnormal Occurrence Report Soi 50-219/75/16 Page 2

- The "as found" and "as Icft" switch settings were:

Associcted "As Found" "As Left" Switch Valve Setting Setting 1A83A NR108A 1077 psig 1079 psig 1A83B NR108B 1089 psig 1084 psig 1A83C NR108C 1077 psig 1077 psig 1A83D NR108D 1082 psig 1082 psig 1A83E NR108E 1085 psig 1081 psig APPARENT CAUSE X Design Procedurc 0F OCCURRENCE: Maaufacture Unusual Service Condition Installation / Inc. Environmental Construction Component Failurc Operator Other (Specify)

Instrument drift has been tentatively identified as the cause of this occurrence.

ANALYSIS OF The relief valves are provided to remove sufficient energy OCCURRENCE; frcm the primary system to prevent the safety valves from lifting during a transient. The limiting pressure transient' is that which is produced upon a turbine trip from rated design power with a failure of the bypass systen to function.

Under these conditions, the five (5) relief valves are required to operate in order to prevent reaching the lowest set point of the primary systen safety valves. It should bc noted that a 25 psig nargin exists between the resulting peak pressure and the lowest safety valve set point as added assurance that the i

safety valves will not lift during this transient. With valves NR10SB and NR10SE actuating at 5 psig and 3 psig, respectively, above the maximum allowable trip point of 1070

( psig, and assuming the most limiting pressure transient had

Abnorm 1 Occurrenec Page 3 i:cport *,';ct. 50-219/75/16 (

occurred, the lowest set point safety valve or valves may have been required to actuate in order to limit the pressure transient. Since the safety valvo capacity is based upon providing sufficient vessel over-pressure protection upon failure of all pressure release devices, in addition to a failure of the reactor to scram, over-pressurization of the vessel would not have occurred.

CORRECTIVE ACTION: The involved pressure switches, IA83B and 1A83E, were immediately reset to trip at allowabic pressure Icvels.

FAILURE DATA: thnufacturer data pertinent to these switches are as follows:

Manufacturer - Dresser T)Te 1539VX Scrial Nos. - EK3339 (IA83B)

BN7126 (IAS3E) t Prepared by:  :, )\ e.m [ .Date:- b \% 1'(

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To: - James P. O'Reilly /

Directorate of Regulatory Operations Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 FRCH: Jersey Central Power G Light Cocpany

. Dyster Creek Nucicar Generating Station Docket 85 Forked River, New Jersey 08731 W ECT. Abnorsal Occurrence Report No. 50-219/75/_ 16 i The following is a prilininary report being l

submitted in compliance with the Technical Specifications, paragraph 6.6.2.

11mina Approval:

M & G bt.f:8' J. T. Carroll J r. Date CC: Mr. A. Clasbusso 1

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O O Initial Telephone Date of 6/14/75 Occurrence: 6 14 75 Report Date:

-I Initial Written Time of 6/16/75 Occurrence: 0200 Report Date:

OYSTER CREEK h1K* LEAR CENERATING STATIOM FORKED RIVER, NEW JERSEY 08731 Abnormal Occurrence Report No. 50-219/75/1 6 IDENTIFICATION Violation of the Technical Specifications, paragrsqh 2,5.

l OF OC/JRFDCE:

Electromatic Relief Valve Pressure Switches,1A83B and 1A83E, were found to trip' at pressures in excess of the x '

==v4== allowable value of 1070 psig.

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'Ihis event is considered to be an abnormal occurrence as fined in the Technical Specifications, paragraph 1.15A.

Steady State Power Routine Shutdown CONDITIONS PRIOR Operation 1D OCCURRENCE: Hot Standby Cold Shutdown __-

icad Char.ges During Refueling Shutdown Routine Power Opera Routine Startup K Other (Specify)

Operation

- ,The reactor mode switch was in the REFUEL position with reactor coolant temperature less than 212'F.

DESCRIPTION OF On Saturday, June 14, 1975, while performing surveillance OCCURRENCE:

l five Electromatic Relief Valve Pressure Switches, it was that 1A838 and 1A83E tripped at 1089 psig and 1085 psig.

respectively. These values are in excess of the maximum allowable trip points of 1084 psig and 1082 psig, respect which are derived by adding appropriate head correction f actors to the Technical Specification limit of 1070 psig It is noted here that switches 1A835 and 1A83E are associ with valves NR1088 and NR108E, respectively.

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4 O O Abnormai Occurrence Re7ert No. 50-219/75/16 Part 2 l

The "as found" and "ss left" switch settings were:

Associpted "As Found" " 4 inft" S wi t ch Valve SettiaL Sectimc iMn NR108A 1077 psig 1673 psig 1ABJB NR1088 1089 psig 1084 ysig 1A83C NR103C 1077 psig 1077 psig 1MGD NR108D 1082 psis 17.dt2 girJg 1A83E NR108E 1085 psig Ital pAig APPARET CAUSE X Design Procedure OF OCCURRDiCE: Hanufacture (?nusual Service Condit Instt11ation/ [nc. Envir==*"

Construction Component Failure OPelstor _

Other (Specify)

Insttunent drift has been tentatively identified as de of this occurrence, ANAIXSIS OF The relief valves are provided to remove sufficient energy OOCUTG&2 ICE:

1Crom the primary, system to prevent the safety valves fsts lifting during a transidnta. The limiting pressure transias is that which is produced upon a turbine trip from rated design power with a failure of the bypass system to functic Under these conditions, the five (5) relief valves are requ to svperate in order to prevent reaching the lowest set pela of the primary system safety valves. It should ba xetzd th 25 psig margin exists between the resulting peak pressure the Itmest safety valve set point as added assursace ther saftty valves will not ift during this transient Mi.th valves NR10$8 and NR108E sctuating at 5 psig and 3 gsig, respectively, above the maximum allowable trip point of 107 psis, and assuming the most limiting pressure transtecrt haa

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s Abnormal Occurrence Page 3 Report No. 50-219/75/16 occurred, the lowest set point safety valve or valves umry have been required to sc.ruste in order to limit the p transient. Since the safety valve capacity is based-providing sufficient vessel over-pressure protection upon failure of all pressure release devices, in additico to 'a fatture of the reactor to scran, over-prezz.risstice, cf vessel would not have Occus sa.

CORRECTIVE ACTION: 1he involved pressure switches, IA838 and 1A83E, neces immediately reset to trip at allowable pressure Levels-FA11J.QE MTA: Enufacturer data pertinent to these switches are as l'o11 Manufacturer - Dresser Type ,

- 1539VX Serial Nos. - BK3339 (IAS3B)

EN7126 (IA83E) ee k g 4 N _ ,

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