ML20031G920
| ML20031G920 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 10/15/1981 |
| From: | Koester G KANSAS GAS & ELECTRIC CO. |
| To: | Madsen G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8110260208 | |
| Download: ML20031G920 (4) | |
Text
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1 KANSAS GAS AND ELECTRIC COMPANY TH ELFCTEUC COMPANY h0$%,
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Mr. G.L. Madsen, Chief
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4,/Pr7 Reactor Projects Branch Q,-
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Region IV
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KMLNRC 81-127 Re:
NRC Docket No. STN 50-482 Ref: Initial Rep irt dated August 13, 1981, transmitted by GLKoester (KMLNRC 81-105) to CLMadsen, NRC Subj: Final 50.55(e) Report - GE AKR Circuit Breaker Screws
Dear Mr. Madsen:
On July 14, 1981, Kansas Gas and Electric Company made a telephone report to Mr. W. A. Crossman (NRC) regarding loose and/or bent screws in the closing mechanisms of GE AKR circuit breakers. These screws, when displaced, have the potential for prever. ting the breaker from closing. An initial report was provided by the j
Reference.
s As indicated in the Reference, please find attached a final report submitted pursuant to 10CFR50.55(e) regarding the GE AKR Circuit Breaker Screw deficiency.
Please advise us if you require anv additional information.
Yours very truly,
' ggy
- lU GLK:bb Attach cc: TVandel, NRC Resident Inspector Attach 8110260208 811015 DR ADOCK 05000482 ffb PDR 5, !
201 N. Market - Wichita, Kansas - Mail Address: PO. Box 208 I Wichita, Kansas 67201 - Telephone: Area Code (316) 2616451 l
Attachment to
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KMLNRC 81-127 Dated Oct. 15, 1981 I
'OCFR 50.55(e) FINAL REPORT On GE ACR CIRCUIT BREAKER LOOSE SCREWS For WOLP CREEK GENERATIt)G STATION, UNIT NO. 1 October 15, 1981 2
1 of 2 l.0 INTRODUCTION On July 14, 1981, Kansas Gas & Clectric Company made a telephonc
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report to Mr.
W.
A. Crossman (N RC, Region IV) concerning the discovery of loose and/or bent screws in the closing mechanisms of GE AKR Breakers.
2.0 DESCRIPTION
OP DEFICIENCY A 1/4-20 flat head screw + hat secures the charging spring crank onto the cam shaft is able to work loose. Once loose, the crank drops onto the screw (of f the shaft) causing the screw to bend.
This deficiency can af f ect proper operation of the breaker during closing, and can result in failure to close on demand.
3.0 IDENTIFICATION OF FIRM SUPPLYING C MSS IC AKR 30/50 LOW VOLTAGE POWER CIRCUIT BREAKERS The Class IE Low Voltage circuit Breakers were supplied by General Electric Company, issued under Bechtel Purchase Order 10466-E-017.
4.0 SAFETY IMPLICATION There are 129 breakers affected at the Wolf Creek Generating Static 7 Of these, 42 are in safety systens which are fed by C1t..us IE load centers.
If the following corrective actions had not been implemented, then the loose screws in the closing nochanism had the potential to prevent the breaker from closing on demand, thus, degrarling the safety of the plant.
5.0 CORRECTIVE ACTION The architect / engineer reviewed and approved thc vendor's inspection and adjustment procedure (GE No. WC-19, Rev.
. lated 8/6/81) for the AKR 30/50 Low Voltage Pov:er Circuit Breaker's closing spring and link assemblies.
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,,e' 2 of 2 An a result of field irnplementation, a further revinion of the vendor's
.innimetion and ad justruent. procedure (GE No. WC-19, Rev. 3 dated 9/14/81) was required. Upon implementation of the approved vendor's inspection and adjusitaent procedure (GE No. WC-13,14ev, 4 dated 9/17/81), it was dincovered that approximately 10 percent of the breakers could not be adjusted according to the approved inspection and c.djustment procedure due to an excessive number of r.hirus preventing the crank f rom firmly sitting against the cam shaft.
The architect / engineer reviewed and approved the vendor's repair and adjustment procedure (GE No. WC-21, llev. O dated 9/29/81) f - these.
breakers with excessive shims. St rt-up Pield Reports (SFRu) NG-2, NG-3, and NG-4 are being uned to document the vendor's repair and adjustment procedures to all Class 10 AKR 30/50 Low Vo;tage Power Cf cuit Dreakers.
All Class II: AKH 30/50 Low V0ltaqe Power Circuit Breakers have. been placed on Sold until the vendor's inspection rep u and adjustment procedures have been fully implemented and documented.
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