ML19324C175

LER 89-012-01:on 890309,diaphragm Leak Found in Pressure Differential Switch 1E31-N013BB.Caused by Tear Found in Diaphragm.Replacement Switch Installed,Calibr & Functionally Tested satisfactorily.W/891108 Ltr

ML19324C175
Person / Time
Site:	LaSalle
Issue date:	11/08/1989
From:	Diederich G, Tennyson M COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
IEB-86-002, IEB-86-2, LER-89-012, LER-89-12, NUDOCS 8911150129
Download: ML19324C175 (5)

Text

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I x Commonwealth Edison

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-) RuralRoute #1, Box 220LaSalle County Nucl:ar Station

' v Marselfles, Illinois 61341 l Telephone 815/357 6761 j J

Wovember 8, 1989 2 i

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Director of Nuclear Reactor Regulation .

U.S. Wuclear Regulatory Commission  !

Mail Station F1-13*l {

Washington, D.C. 20555 Daar Sir  ;

Licensee svent Report 649-012-01. Docket #050-373 is being  :

sutaitted to your office to supercede previously submitted [

Licensee Event Report 88-012-00 which was reported .

I pursuant to NRC I.3. Bulletin 86-02. " Static-O-Ring Differential Pressure switches." ,

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G. J. DiederHch (t/ Station Manager  !

LaSalle County Station  !

GJD/ tert /kg Enclosure j t

xc: Wuclear Licensing Administrator NRC Resident Inspector ,

WRC Region III Administrator l

INPO - Records Center o

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.8911150129 891109 t FDR ADOCK 06000373 s PDC

vl LICENSEE EVLWT C2 PORT (LER)  % Rev 2.0 Docket thater (2) Pane (3)  !

facihtyName(1)

LaSa11e County station unit 1 01 51 01 01 01 31 71 3 1lof!0l4 title (4) j

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Anactor Core Isolation Coolina Mi Steam Flow Isolation Switch Failed Olanhram LER thauber (61 Resort Dato (7) Other Facilities Involvec (8) l Event Date (5) _ Docket thauber(s) i Year Year /n Sequential /n Revision Month Day Year Fact 11tv Names Month Day fy

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01 1 i111 01 e el 9 01 51 01 01 01 1 I l el 3 01 9 el 9 el 9 01112 THis REPORT 15 $USMITTED PURSUANT TO THE REQUIREMENTS OF 10CFR OPERATlw (Check one or iiirse of tue followinn) (11) g 20.405(c) 50.73(a)(2)(iv) 73.7)(b) 1 20.402(b) ,_, ,_ ,,,,,_

20.405(a)(1)(i) 50.M(c)(1) ,,,,, 50.73(a)(2)(v) ,_,,, 73.71(c)

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11 01 0 20.40$(a)(1)(lii) 50.73(a)(2)(1) 50.73(a)(2)(viii)(A) in Abstract ,

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l llCE SEE CONTACT FOR THis LER (12) ,,,

1ELEPHONE WUSER j Name '

AREA CODE Michael Tennyson. Technical Staff Enaineer. extension 2704 8 l 1 15 31 51 71 -l td 11 61 1 wiFLETE ONE LINE FOR EACH CfDFONEN F AILURE DESCRISED IN YHis REPORT (13)

CAUSE SYSTEM C090NENT MRNUFAC- REPORTABLE CAUSE SYSTEM C0@0NENT MANUF AC- REPORTABLE YURER TO NPflDS TURER TO NPR0$_ '

51 31 81 2 Y l l l l l l l X Rl 1 l l FI 5 I i l i I I i i I I I I l I I Expected Month i Day i Year ,

$UPPLOOTAL REPORT EXPECTED (14)

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ABSTRACT (Limit to 1400 spaces, i.e, approximately fifteen single-space typewritten lines) (It>)  :

On March 9,1999, at 2045 hours0.0237 days <br />0.568 hours <br />0.00338 weeks <br />7.781225e-4 months <br />, during perfomance of LaSalle instrument survet11ance L15-RI-101,

• Unit 1 Steam Llhe High Flow Reactor Core Isolation Cooling (RCIC) llolation Calibration 41 Test," Pressure Olfferential switch 1E31-4101308 was found to have a diaphrayn leak. Unit 1 was in operational condition 1 (Run) at 100E power level. The setpoint for this switch was found within the action limit and the Limiting Condition for Operation (LCO).

This switch functions with siellar switch 1E31-4f013tA, to provide Olvision 11 (Inboard) isolation of the RCIC/ Residual Heat .lsmoval Stem Line and to initiate a RCIC turbine trip.

1E314001308 is connected in reverse parallel to IE31-41013tA. The design function of IE31-4f01388 is to initiate an inboard containment isolation in the event of an instronent line break. Particularly a break in the instroent inne caning frten the high pressure side of the steam flow elbow leading to the high pressure side of IE31-48013tA and to the low pressure side of 1E31-af01308. RCIC system had been declared inoperable on March 9,1999 at 1300 hours0.015 days <br />0.361 hours <br />0.00215 weeks <br />4.9465e-4 months <br /> in order to perfom the required survel11ance. The High Pressure Core Spray system remained operable throughout the duration of this event.

A replacement switch was installed, calibrated and functionally tested sattifactorily. RCIC system was declared operable on March 10, 1989 at 1940 hours0.0225 days <br />0.539 hours <br />0.00321 weeks <br />7.3817e-4 months <br />. The replaced switch was disassembled and inspected on October 5, 1999. The cause of failure was due to a tear found in the diaphrayn.

This event is reported to the Nuclear Regulatory Comnission as a Licensee Event Report in accordance with the requirements of 1.E. Bulletin 96-02, ' Static-0.-Ring (50R) Differential Pressure Switches."

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• Form Rev 2.0  !

'a LP""E EVENT %"2T (LER) TERT CONillalAfini '

DOCKET ImpSER (2) LER 1RBSElt (6) Paas Cl) l FACILOT IIAfE (1)

Revision i Year /// Sequential ffj

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hkaber  ;

0l112 01 1 01 2 01 4 [

'*hile County station unit 1 015101010131713 8I9 - - UF l

TEXT Energy industry identification System (Eltl) codes are leentlflod in the test as (XX) {

T PLANT MID SYSim 10EWilFICAtl0N teneral Electric . Solling Water Reactor f Energy Industry identification System (Ell 5) codes are Ideutified in the test as [XX). l i

A. CONDITION PRIOR 10 EVENT l

t Event Date: 3/9/99 Eve'nt ilme: 2045 Hours Unit (s): 1 1005 j Reactor Mode (s): 1 Mode (s) Name: Run Power Level (s): .

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S. DESCRIPi10N OF EVEN1  !

Reactor Core Isolation Cooling (RCIC, RI) [9N) Stem Line High Flow Isolation (PC) [JM) Swltch 1E31-4101338 was found to have a diaphragm leak on march 9, 1999 at 2045 hours0.0237 days <br />0.568 hours <br />0.00338 weeks <br />7.781225e-4 months <br />. The problem was 6.oted ,

whlie a r.allbrational test was being performed per LaSalle Instrument Surveillance L15-RI-101, ' Unit 1

'Ste m Line High Flow RCIC isolation Calibration fest." This survel11ance calls for verifying that the i diaphrapn does not leak in addition to verifying that the proper actuations occur at the proper setpoints. During this surveillance, the Instroent Maintenance Technician (C51) found the setpoint [

within the Action Limit and Limiting Condition for Operation (LCO) for this instrument. RCIC had been declared inoperable per Degraded Equipment Log (DEL) thaber 90-09-1, prior to the start of the j

. survelliance.

1E3141013tB works in parallel with differential switch 1E31-40013tA to trip the RCIC turbine and I autsmatically close the *RCic Steam Line inboard Isolation valve" (IE514063) and the *RCic Stem Line j Warnup Valve" (IE514076). A high differential pressure condition for either IE31-410130A or I P05-1E31410130s will cause an actuation to take place. i 1E3141013er, is connected in reverse parallel to 1E31-4f013tA. The design function of IE314101308 is to i Initiate an inboard contalraent isolation in the event of an instrument line break. Particularly a  !

break in the instroent ilne caming from the high pressure side of the stem flow elbow leading to the ,

high pressure side of 1E31-40013tA and to the low pressure side of IE31-4f01308. l -

Ito other inoperable equipment / systems contributed to this event. No automatic or' manual safety system j

actuations occurred and none were required. 100 Operator actions contributed to the causation or l

severity of this event. Actions taken to correct the cause of this event were timely and appropriate.

This event is reported to the Nuclear Regulatory Commission as a Licensee Event Report in accordance l l

with the requirements of 1.E. Bulletin 06-02, " Static-0-Ring (50R) Olfferential Pressure Switches." 1 h

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• LlCENSEE EVENT REPORT (LER) TEXT CONiluuRTION DOCKET WuptER (2)' t.ER C R (6) .

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FACILffY NRIE (1) Revision Year /// Sequential /// l fff fff

/// thaber /// thaber {

01112 01 1 of 3 0F of 4 l f 0 1 5 1 0 1 0 1 0 1 31 71 3 eIt - -

LaSalle Countv 5tation unit 1 I

. TEXT Energy Irdustry identification System (Ell 5) codes are Identified in the text as (KK)

C. APPARENT CAUSE OF EVENT The 50R switch was disasseeled and inspected at LaSalle Station on October 5,1999, per LaSalle l Instrument Procedure. LIP-GM-962, "Olsassembly and inspection of SOR Moded 102 and 103 Delta-P Switches.* The cause of LSe switch failure was due to a half-inch tear found on the diaphrap during i the inspection. The root cause of the diaphrap tear could not be detemined.  !

The diaphrap divides the two halves of the differential pressure switch into a 'high" side and a ' low" l

side. As system flow increases, the difference in pressures between the sides of the switch also Increases. This causes the diaphrap to flex. A piston asseely is afflued to the diaphrap and drives a microswltch which trips when the deflection of the diaphragm is sufficient.

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D. SAFE 1Y ANAtV515 0F EVENT A leaking diaphrap of IE31-W01388 would allow for the equalization of pressure between the high and low .

instraent lines. This could prevent switch IE31-#0138A (which uscs the sane instrument lines as IE31-N01388) from sensing any high stem flow condition, or alter its trip setpoint, rendering the switch inoperable. However, when calibrated, the switch did trip at an acceptable trip setpoint, in addition redundant equipment (pressure differential switches 1E31-WO13AA and IE31-4f013A8) remained fully [

operable, and would have provided the outboard Isolation of valve IE51-f006 RCIC outboard Isolation Valve.

I In addition, both the inboard and outboard Isolation functions for Residual Heat Removal (RHR, RH) (90) l stem lifw high flow would have occurred as designed had a high flow condition existed in the RHR stem

( line downstrem of the RHR Heat Exchanger Outboard Isolation Valve, IE51-F064.

The corrective action for this event was perforined as required by Technical Specifications. This resulted in RCIC being declared inoperable. During this ilne, however, High Pressure Core Spray (HPCS, HP)(90)wascperable, t

E. CORRECTIVE ACTIONS l

I Inboarvj isolation valves 1E51-F063 and 1E51-F076 were secured closed prior to the start of the I l

surveillance. The RClc high flow isolation was declared inoperable and the isolaiton valves remained closed. )

l RCic was entered as inoperable in the Degraded Equipment Log (DEL) Weber 90-89-1. Action Statement b.

' of Technical Specification 3.7.3 allows fourteen days to restore operability to RCIC, provided HPCS remains operable.

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.e LLem!E EVENT Rfe0RT (LER) TEXT CONTINuRTION Form Rev 2.0 LER NUSER (6) Paes (3)

FACILITY NM (1) DDCKET NUMER (2)

Year fy/

/ 5equential /j/j/ Revision

/// thauber j/// thster 0 1 5 1 0 1 0 1 0'l 31 11 3 819 - 01112 - 01 1 01 4 0F 01 4 4 i m ite Countw Station unit 1 TEXT Energy Industry identification System (E!!$) codes are identified in the test as (XX]

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E. CORRECTIVE ACTIONS (Continued)

A new 50R differentla) pressure switch identical to the one that failed was certified for use in the i RCIC stem line high flow appilcation using LIP-On-952, *5tatic44 lng Olfferential Pressure Switch This  :

operability Test," and LIP.4M-956, " Analysis of Static 44tng Olfferential pressure switch Data."  ;

new switch was installed per LIP-OR-946, " Installation Procedure for 5-0-A Model 103/100 Environmentally Quellflod Olfferential Pressure Switches," under LaSalle Wort Request L84100 on March 10, 1999. The switch was calibrated per L15-RI-101, " Unit 1 Stem Line High Flow RCIC isolation Ctllbration."

Operability was restored to RCIC on March 10, 1999 at 1940 hours0.0225 days <br />0.539 hours <br />0.00321 weeks <br />7.3817e-4 months <br />. .

3 F. PREVIOUS EVEN15 ,

LER ths6er Title I

314/0641841 Failure of Reactor Core Isolation Cooling Steam Line Flow Isolation Switch Due to Torn Olaphrap 374/8741641 Defective Low Pressure Core Spray Mininsa flow Switch  :

i 314/g1419-01 Failure of Static 4-Ring Differential Pressure Switch Due to Leakage Across Olaphrap 373/08-009-01 High Pressure Core Spray Low Low Level initiation Static 4-Alng Level Switch Olaphra p Rupture i

G. Co@0NENT FAILURE DATA i Nomenclature Model Number MFG Part ths6er Manufacturer  ;

103AS42034X N/A 50R, Inc. Olfferential e Pressure Switch JJTTX6 r

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