ML20072C644
| ML20072C644 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 05/26/1983 |
| From: | Woolever E DUQUESNE LIGHT CO. |
| To: | Allan J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, 2NRC-3-035, 2NRC-3-35, 83-03, 83-3, NUDOCS 8306210141 | |
| Download: ML20072C644 (5) | |
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$VL 2NRC-3-035 (412)787 - 5141 (412)923 -1960 Telecopy (412) 787-2629 May 26,1983 Nuclear Construction Division Hobinson Plaza, Building 2. Suite 210 P!ttsburgh, PA 15205 United States Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406 ATTENTION:
Mr. James Allan Act ing Administrator
SUBJECT:
Beaver Valley Power Station - Unit No. 2 Do cke t No. 50 -412 Potential for Misoperation of DS-416 Reactor Trip Switchgear Undervoltage Attachments Significant Deficiency Report No. 83-03 Gentlemen:
This Interim Report is in reference to the potential for misoperation of DS-416 reactor trip switchgear undervoltage at t achme nt s repo rt ed to the Nuc le ar Regulatory Commission by S. D. Hall of Duquesne Light Company (DIE) on April 26, 1983.
DLC is presently evaluating infonnation received from Wes tinghouse with regard to the impact of this problem on Beaver Valley Unit No. 2.
Pursuant to the requirement s of 10CFR50.55(e), it is anticipated that a subsequent repo rt on this matter should be submitted to Region I by September 1, 1983.
DUQUESNE LIGHT COMPANY By E. J. Wooleve r Vice President SUBSCRIBED AND SKORN TO BEFORE ME THIS
,_2 WDAY OF
/2/.d
, 1983.
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L.
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"7 Notary Public ELVA G. LESONDAK, NOTARY PUBLIC
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RCBiNSON TOWNSHIP, ALLEGHENY COUNTY MY COMM'SSION EXPIRES GCTOSER 20,1986 8306210141 830526 DR ADOCK 05000 4 tu
United Stcteo Nuclocr Rsguletory Commission Mr. James Allen page 2 JMM/wjs At tachment cc:
Mr. G. Walton, NRC Resident Inspector (w/a)
Ms. L. Lazo, NRC Project Manager (w/a)
NRC Document Control Desk (w/a)
Mr. R. DeYoung, Director Of fice of Inspection and Enforcement (3) (w/a)
INPO Records Center (w/a)
COMMONWEALTH OF PENNSYLVANIA )
)
SS:
COUNTY OF ALLEGHENY
)
On this jd day of
/
, before me, a Notary Public in and fo r said [ommonwealth and County, pe rso nally appe ared E.
J.
Wooleve r, who be ing duly swo rn, deposed and said that (1) he is Vice Pres ident of Duquesne Light, (2) he is duly au tho rized to exe-cute ani file the foregoing S ubmit tal on behalf of said Company, and (3) the statements set forth in the S ubmittal are true and correct to the bes t of his knowledge.
/
' flot ary Pub lic ELVA G. LESONDAK, NOT ARY PUBLIC ROBINSON TOWNSHIP, ALLEG' ENY COUNTY MY COMMtSSION EXPIRES OCTOBER 20,1936
Unitsd Sttteo.Nucisar Ragulatory Commission Mr. James Allen page 3 bec: R. Coupland (w/ attachment)
C. E. Ewing' T. J. Lex (4)
J. M. Markovich NCD File J. Pedro (NUS)
P. RaySircar (3)
G. M. Schierbe rg (S&W)
J. Sutton (S&W)
J. F. Zagorski C. R. Bishop (w/o attachments)
T. D. Jones H. M. Siegel R. J. Swiderski D. H. Williams
REFERENCES:
(1) Significant Deficiency Report No. 83-03 (2) DMW-D-3 395, da t ed April 21,
- 1983, DS-416 Re acto r Trip Switchgear 10CFR50.55(e) Reportable Issue" g
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'o BEAVER VALLEY POWER STATION - UNIT NO. 2 DUQUESNE LIGHT COMPANY Interim Report No.1 on the Potential for Misoperation of DS-416 Reactor Trip Switchgear Undervoltage Attachments
.1.
SUMMARY
On March 30, 1983, Westinghouse (W) advised af fected operating plants of the pot ent ial for.misoperation of DS-416 reactor trip switchgear under-reported malfunctions at one plant ' during volt age at t achment s based on testing.
W advised operating plants on April 15, 1983, of an additional misopera-t ion of another DS-416 undervolt age at t achme nt.
Investigation of this event revealed a missing retaining ring on one of the two undervoltage attachment pivot shafts.
2.
IMMEDIATE ACTION TAREN On April 20, 1983, W advised the Nuclear Regulatory Commission (NRC) of the pot ent ial for mIsoperation of DS-416 reactor trip switchgear under-volt age at t achme nt s.
S.
D. Hall, Duquesne Light Company, 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 THE DEFICIENCY Based on repo rt ed malfunctions at one plant during tes t ing, W advised a f fect ed operating plants on March 30, 1983, of the pot ent ial for mis-
. operation of DS-416 reactor trip switchgear undervolt age attachment s.
W began an evaluation of the input from several af fected operating plant s concerning dimensions of-several cle arances in the unde rvo lt age attachment.
On April 15, 1983, W advised operating plants of an additional misopera-another DS 416 undervoltage at t achme nt.
Inves tigation of this T
t ion of event revealed a missing retaining ring on one of the two undervoltage a t tachment pivot shafts.
This allowed the pivot shaft to move laterally such that one end came ' out of its guide hole in the frame of the under-volt age at t achme nt, and did not pe rmit the at tachment to ope rate on demand.
4.
ANALYSIS OF SAFETY IMPLICATION' W evaluated the input from several af fected operating plant s conce rning dimens ions of several cle arances in the unde rvo lt age at tachme nt ani concluded that deviations from the' recommended clearances could increase the pot ent ial for misope ration of the at t achme nt, thereby creat ing a condition wherein the reactor trip switchgear might not open on automatic demand from the reactor protection system.
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The W evaluation of the retaining ring issue revealed a discrepancy in design.
The groove in the shaft receiving the ret aining ring was not increased in width to be consistent with an earlier (1972) retaining ring design change.
The new retaining ring is wider than the original design and does not seat prope rly in the exis ting groove s.
This disc repancy increases the pot ent ial for misope rat ion of the DS-416 unde rvo lt age a t t achme nt, thereby creating a condition wherein the reactor trip switch-gear ' might not open on automat ic demand from the reacto r prot'ect ion system.
5.
CORRECTIVE ACTION TO REMEDY DEFICIENCIES BVPS-2 is currently evaluating the potential for misoperation of the DS-416 undervolt age at t achme nt.
When furthe r de t ails conce rning this problem are available, BVPS-2 will issue another report.
6.
ADDITIONAL REPORTS BVPS-2 will issue another report on this matter when further details of the evaluat ion are availab le.
It is expect ed that this repo rt will be issued to Region I by September 1,1983.
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