ML18092A966
| ML18092A966 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 12/06/1985 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML18092A965 | List: |
| References | |
| GL-83-28, NUDOCS 8601020536 | |
| Download: ML18092A966 (4) | |
Text
----------------------------
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO REACTOR TRIP SYSTEM RELIABILITY
- l.
INTROOUCTI ON ITEMS 4.2.1 AND 4.2.2 OF GENERIC LETTER 83-28 PUBLIC SERVICE ELECTRIC AND GAS COMPANY PHILADELPHIA ELECTRIC COMPANY DELMARVA POWER AND LIGHT COMPANY, AND ATLANTIC cITY ELECTRIC COMPANY SALEM NUCLEAR GENERATION STATION, UNIT NOS. 1 AND 2 DOCKET NOS. 50-272 AND 50-311 0 n J u l y 8, l 9 8 3, t he Nu c l ea r. Reg u l a ~or y C onrn 1 s s 1 on ( N RC ) 1 s s u e d Gener1c Letter (GL} 83-28.
Th1s letter addressed 1ntermed1ate-term act1ons t~ be taken by l1censees and appl1cants a1med at assur1ng that a comprehens1ve program of prevent1ve ma1ntenance and surve1llance test1ng 1s 1mplemented for the reactor tr1p breakers (RTBs) 1n pressur1zed water reactors.
In part1cular, Item 4.2 of the letter requ1red the 11censees and appl1cants to subm1t a descr1pt1on of the1r prevent1ve ma1ntenance and surve1llance program to ensure rel1able reactor tr1p breaker operat1on.
The descr1pt1on of the subm1tted program was to 1nclude the follow1ng:
GL, Item 4.2. l GL, Item 4. 2. 2 A planned program of per1od1c ma1ntenance, 1nclud1ng lubr1cat1on, housekeeplng, and other 1tems reconrnended by the equ1pment suppl1er.
Trend1ng of parameters affect1ng operat1on and measured dur1ng test1ng to forecast degradation of operat1on.
Publ1c Serv1ce Electr1c and Gas Company, the 11censee for Sal~m l and 2, subm1tted responses to the Gener1c Letter on July 8, 1983, and August 19, 1985.
Th1s report presents an evaluat1on of the adequacy *of those responses and of the 11censee's prevent1ve ma1ntenance and surve1llance programs for RTBs.
i 8601020536 851206
-~-':
I PDR'
- ADOCX 05000272.
- i p
PDR I
- 2.
EVALUATION CRITERIA 2.1 Per1od1c Ma1ntenance Program The pr1mary source for per1od1c ma1ntenance program cr1ter1a 1s West1nghouse Ma1ntenance Program for DB-50 Reactor Tr1p Sw1tchgear,-
Rev. 0.
Th1s document 1s the breaker manufacturer's recorrmended ma1ntenance program for the DB-50 breaker and prov1des spec1f1c d1rect1on w1th regard to schedule, 1nspect1on and test1ng, clean1ng, lubr1cat1on, correct1ve ma1ntenance and record keep1ng.
The document was rev1ewed to 1dent1fy those 1tems that contr1bute to breaker tr1p rel1ab111ty cons1stent w1th the gener1c letter. Those 1tems 1dent1f1ed for ma1ntenance at s1x month 1ntervals that should be 1ncluded 1n the 11censee's RTB. ma1ntenance program are:
- 1. Ver1f1cat1on of tr1p bar freedom
- 2.
Ver1f1cat1on of operat1ng mechan1sm al1gnment and freedom
- 3.
Reta1n1ng r1ng ver1f1cat1on
- 4.
Ver1f1cat1on of nut and bolt t1ghtness
- 5.
Ver1f1cat1on of pole bases phys1ca1 cond1t1on
- 6.
Ver1f1cat1on of arc1ng and ma1n contacts phys1,al cond1t1on
- 7.
Ver1f1cat1on of 1nsulat1ng 11nk's phys1cal cond1t1on
- 8.
Ver1f1cat1on of w1r1ng 1nsulat1on and term1nat1on phys1cal cond 1t 1 on
- 9.
Ver1f1cat1on of arc chute phys1cal cond1t1on
- 10.
Ver1f1cat1on of breaker cleanl1ness
- 11.
Undervoltage Tr1p Attachment (UVTA) dropout voltage test and lubr1cat1on
- 12.
Shunt Tr1p Attachment (STA) operat1on ver1f1cat1on
- 13.
Ver1f1cat1on of operat1on of aux111ary sw1tches
- 14.
Inspect1on of pos1t1on1ng lever cond1t1on
- 15.
Funct1onal test of the breaker pr1or to return1ng 1t to serv1ce.
2
The 11censee's RTB per1od1c maintenance should also 1nclude, on a refuel1ng 1nterval bas1s:
- 16.
Ver1f1~at1on of cell 1nterlock operat1on
- 17.
Exam1nat1on and clean1ng of breaker enclosure
- 18.
Measurement of tr1p force requ1red
- 19.
Funct1onal test of the breaker pr1or to return1ng 1t to serv1ce
- 20.
Breaker response t1me for undervoltage tr1p.
All of the 1tems 11sted above are reconmended by the manufacturer except Item 20.
Th1s 1lem 1s the breaker tr1p response t1me measurement wh1ch 1s 1mpl1ed by the IEEE Standard 279-1971.
2.2 Trend1ng of Parameters Gener1c Letter Item 4.2.2 spec1f1es that the 11censee's preventative ma1ntenance and surve11lance program ls to 1nclude trend1ng of parameters affect1ng operat1on and measured dur1ng test1ng to forecast degradat1on of operation.
The parameters measured dur1ng the maintenance program described above wh1ch are applicable for trend1ng are undervoltage tr1p attachment dropout voltage, trip force, and breaker response t1me for undervoltage tr1p~ The staff pos1t1on 1s that the above three parameters 1n add1t1on to the breaker 1nsulat1on res1stance are acceptable and reconmended trend1ng parameters to forecast breaker operation degradation or fa1lure.
If subsequent experience 1ndicates that any of these parameters ls not useful as a tool to anticipate fa1lures or degradation, the 11censee may, w1th just1f1cat1on and NRC approval, elect to remove that parameter from those to be tracked.
- 3.
EVALUATION 3.1 Evaluation of the L1censee Pos1t1on on Item 4.2.1 The 11censee states that h1s preventat1ve ma1ntenance program for RTB's has been rev1sed to contain all the elements deta11ed 1n Sect1on 2. 1 3
(
,J.
Jj
' " ~. (,
of th1s SER, w1th the ma1ntenance to be performed at least at the ~requency spec1fled there1n.
The staff flnds the llcensee pos\\t\\on on Item 4.2. l to be acceptable.
3.2 Evaluat1on df the L1censee*s Pos1t1on on Item 4.2.2 The 11censee states that h1s trend analysls program for the RTBs 1ncludes performance of trend analys1s of tr1p force, breaker response t1me, undervoltage tr1p dropout voltage and 1nsulat1on res1stance, as well as several other parameters.
The 11censee has 1dent1f1ed the organ1zat1on wh1ch w111 perform trend analys1s, how often 1t w111 be performed and how the 1nformat1on der1ved from the analys1s w111 be used to affect per1od1c ma1ntenance.
The staff f1nds the 11censee pos1t1on on Item 4.2.2 to be acceptable.
- 4.
CONCLUSIONS Based on a rev1ew of the 11censee responses, the staff f1nds the 11~ensee pos1t1ons on Items 4.2.l and 4.2.2 of Gener1c Letter 83-28 to be acceptable.
DATED: December 6, 1985 PRINCIPAL CONTRIBUTOR:
N*. Romney 4