ML20080A349
| ML20080A349 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 01/05/1984 |
| From: | Woolever E DUQUESNE LIGHT CO. |
| To: | Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| 2NRC-3-106, 83-03, 83-3, NUDOCS 8402030467 | |
| Download: ML20080A349 (4) | |
Text
!
I e
- jme, 7%
(412) 787 - 5141 Telecopy
-o Nuclear Construction Division January 5, 1984 Robinson Plaza, Building 2, Suite 210 Pittsburgh, PA 15205 United States Nuclear Regulatory Commission Regica I 631 Park Avenue King of Prussia, PA 19406 ATTENTION:
Mr. Richard W. Starostecki Division of Project ard Res ident Programs
SUBJECT:
Beaver Valley Power Station - Unit No. 2 Docket No. 50-412 Pot ent ial fo r Misope ra t io n of DS-416 Re act o r Trip Switchge ar Unde rvo it age At t achment s Significant Deficiency Report No. 83-03 Gentlemen:
Purs uant to the req ui rement s of 10 CFR50.5 5 (e), the " Final Report on the Potent ial for Misoperation of DS-416 Reactor Trip Switchgear Undervolt age A t t achme nt s" is at t ach ed fo r your review.
If there are any ques t ions con-cerning this report, please cont act the Beaver Valley Unit 2 Project Of fice.
DUQUESNE LIGHT COMPANY By
[
~E (fJ."Wooleve r JMM/wjs Vice President At t achment s cc:
Mr. R. DeYoung, Director Of fice of Inspect ion and Enforcement (3) (w/ attachment s)
Mr. G. Walton, NRC Resident Inspector (w/ attachments)
Ms. L. Lazo, Project Manager (w/ attachment s)
NRC Document Control Desk (w/ attachments)
INPO Records Center (w/ attachment s)
SUBSCRIBED AND WORN TO BEFORE ME THIS Sf/DAYOF Jgrunu 1984.
f
/&
iv Not ary Public ANIT A ELAINE fiEITER, NOTARY PUBLIC ROEIN3ON TOWNSMiP, ALLECHEMY CCUNTY MY COMMISSION EXFIRES CCTOBER 20,1986 o
n\\
b I 8402030467 840105 U
PDR ADOCK 05000412 S
,g
d ?.
- o United Stcteo Nuclear Regulf. tory Commission 4
Dr. 'thonto E. Murley Page 2 e
COMMONWEALTH OF' PENNSYLVANIA )
) SS
,3 9
-COUNTY 0F ALLEGHENY
)
- On this
[d day of 2/4/4//,
/M[ before me, a Not ary Pub lic in and for ~ said Commonbith and County, personally _ appeared E.
J.
Woolever, who being duly sworn deposed and said that (1) he is Vice -President
~
of Duquesne Light, -(2) he Lis drly authorized.to execute and file the fo re.
going Submittal on behalf of said Company, and (3) the statement s set fo rt h in the1 Submittal are true and correct to the best of his knowledge.
/
Not ary Pub lic ANITA ELAINE REITER, NOTARY PUBLIC ROBINSON TOWNSHIP, ALLEGHENY COUNTY MY COMMISSION EXPIRES OCTOBER 20,1986 1
4
.,,,-cr--
r-re w
~
e,-
,--e
--,aw,.
,e
-m e
,m-,.
e Y
BEAVER VALLEY POWER STATION Uf71T NO. 2 DUQUESNE LIGHT COMPANY Final Report on the Potential for Misoperation of DS-416 Reactor Trip Switchgear Undervo lt age At tachment s 1.
SUMMARY
On March 30, 1983, Wes t inghouse (W) advised af fect ed operating plants of the potent ial for misoperation of DS-416 reactor trip switchgear undervol-t age at t achme nt s based on repo rt ed mal funct io ns at one pla nt during testing.
W advised operating plants on April 15, 1983, of an addit ional misopera-t ion of anot he r DS-416 unde rvo lt age at t achme nt.
Inves t iga t ion of this event revealed a missing ret aining ring on one of the two unde rvo lt age attachment pivot sha f t s.
2.
IMMEDIATE ACTION TAKEN On April 20, 1983, W advised the Nuclear Regulatory Commission (NRC) of the potential for misoperation of DS-416 reactor trip switchgear undervol-t age at t achme nt s.
S.
D.
Hall, Duquesne Light Com pa ny, not ified E.
Brunner, Region I of fice, on April 26, 1983, that an evaluation of this problem for Beaver Valley Unit No. 2 (BVPS-2) was underway.
3.
DESCRIPTION OF DEFICIENCY W advised Based on report ed mal funct ions at one plant during testing, -
af fected operating plants on March 30, 1983, of the pot ent ial for misope r-ation of DS-416 reactor trip switchgear undervoltage at t achment s. W began an evalua t io n of the input fr om several af fect ed ope ra t ing plant s con-cerning dimensions of several clearances in the undervoltage att achment.
On April 15, 1983, W advised operating plant s of a'n additional misopera-t ion of anot he r DS-416 unde rvo lt age at t achment.
Inves t iga t io n of this evcat revealed a missing retaining ring on one of the two unde rvo lt age a t t achment pivot shafts.
This al iawed the pivot shaft to nove la t e ral ly such that one end came out of its guide 1. ole in the frame of the undervol-tage attachment, and did not permit the attachment to operate on demand.
4.
ANALYSIS OF SAFETY IMPLICATIONS W evaluated the input fr om several af fect ed operating pl ant s conce rni ng dimens io ns of several c le arances in the unde rvo lt age at t achme nt and c onc luded that devi at ions from the recommended c learances could inc reas e the pot ent ial fo r misope ra t ion of the at t achme nt, the reb y creating a condition wherein the reactor trip switchgear might not open on automatic demand from the reactor protection system.
The W evaluat ion of the ret aining ring issue reve aled a disc repancy in design.
The gr oove in the shaft receiving the ret a ini ng ri ng was not increased in width to be cons is t ent with an earlier (1972) retaining ring
.s:. S.
e design ch ange. - The - new ret aining ring ~is wider than the original design and ' does. not seat properly in the existing grooves.
This disc repancy increases' the - pot ent ial for micoperation - of the DS-416 unde rvo it age
- att achment, thereby creating a condition wherein the reactor trip switch-gear might not ope n on automatic demand from the reacto r prot ect ion s ys tem.'
5.
CORRECTIVE ACTION TO REMEDY DEFICIENCIE3 Four replacement ~ unde rvo lt age at t achment s will be installed on DS-416 reactor trip switchgear for BVPS-2 prior to initial plant ope ra t io n.
The new attachment s have modified (widened) grooves to ac comodat e the new
- retaining rings.
6.
ADDITIONAL REPORTS This is the final report - on this subject.
No additional reports will be issued.
I