ML20084T957

Interim Deficiency Rept Re Defective Cam Followers in GE Type Sbm Switches.Initially Reported on 760416.Numerous Crazed Switches Found Throughout Plants.Investigation Continuing.All Crazed Switches Will Be Replaced

ML20084T957
Person / Time
Site:	Browns Ferry
Issue date:	05/19/1976
From:	Gilleland J TENNESSEE VALLEY AUTHORITY
To:	Moseley N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20084T956	List: ML20084T953 ML20084T957 ML20084T959
References
10CFR-050.55E, 10CFR-50.55E, NUDOCS 8306240329
Download: ML20084T957 (6)

Text

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Q CHATTANOCGA. TENNESSEE 374ol EFM MX i'76 .4 MAY 191976 ,,g @

k Hr. Norman C. 1% clcy, Director yNgp C 1

Office of Inspection and Enforce::ent 'N,,/d

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U.S. Nuclear Ecgulatory Connission g Region II - Suite 818 230 Feachtree Street,IM. '

Atlanta, Georgin 30303

Dear Mr. Moseley:

BROUNS FEpAY INCLEAR PLNiT UNIT 3 - REPORTABLE DEFICIENCY -

DEFECTIVE CMI IDLLOUERS IN CENERAL ELECIRIC TYPE SEM SUITCIIES Initial report of the subject reportable deficiency was made to G. R. Flingler, NRC-IE, Region II, on April 16, 1976. In compliance with paragraph 50.55(c) of 10 CFR Part 50, we submit the following interin report of the deficiency. ' ~

While conducting a preoperational test on the unit 1 Reactor Core Isolation Cooldng (RCIC) System, a Ccncral Electric type SBli switch i failed; this failure was reported in Licensee Event Report BFAO 50-259/764.

• During the investigation of this deficiency, switches of the sane F*

type have been inspected throughout the plant. The inspection revealed a large number of can followers with a crazed appearance sinilar to the l y

condition described in the enclosed Coneral Electric Company Information 1 Letter SIL No. 155. We have found crazed conditions existing on switches

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which were manufactured outside the dates of manufacture specified in '

the service letter. The condition has been found on switches installed in each of the three Browns Ferry units. The investigation is  ;

continuing. Interin plans include replacement of all crazed switches _

installed in safeguards systems and all switches manufactured during the period defined in the enclosed CE Information Letter.

8306240329 760730 PDR ADOCK 05000259 PDR S

An Equal Opportunity Employer h.

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Mr. Norman c. noseley fdAY 191976 A final report will be prepared once tho investigations and replacements at the plant a a completed.

Very truly youra, J. E. Gillcland Assistant Manager of Power Faclosure CC (Enclosure):

Dr. E. Volgenau, Director Offica of Inspection and Enforecment U.S. Huclear Regulatory Cornission Washington, DC 20555

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March 19,1976 File Tab A SIL No. 155 -

Category 1

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_POSSIBLE FAILURES OF TYPE SBM CONTROL SWITCHES Recent failures of General Electric Type SBM Control Switches have been reported by the original component manufacturer. The application of these switches and PWR)isplants.

widespread throughout operating fossil and nuclear (both BWR The reported failures, however, have been limited to SBM switches installed at fossil plants. It should be noted that, to date, the reported number of failed SBM switches is extremely low, (i.e., approximately 0.03 percent for the quantityof switches manufactured and shipped during the period of concern) and that none of the switch failures have occurred in essential circuits. The purpose of this Service Information Letter (SIL) .

' is to list the affected BWR uperating plants, to define the- conditions causing the problem and to present corrective action recommendations for nuclear application of SBM switches.

DISCUSSI0fl The reported failures of GE 'ype SBM Control Switches have been diagnosed as fracture of the Lexan cam followers (an integral part of the switch). - -

The failures have been attributed to exposure of some Lexan cam followers to hydrocarbons.

of the Lexan material. Contamination by hydrocarbons contributes to degradation This degradation could eventually progress to a fracture of the cam follower in any of the following three modes: resulting in failure of the switch assembly

1. Failure of the switch to open. 4

2. Failure of the switch to close.

3. Jamming of the switch mechanism which would prevent any further action. '

Cam followers in question which have been exposed to the hydrocarbon are a +-

part 1975.

May of SBM switches manufactured during the period from July 1972 through SBM switches manufactured during this time period may be

. s.

1 NUCLEAR ENERGY DlVISION

• OPERATING PLANT SERVICES

• SAN JOSE, CALIFORNIA 95125 '

No WARRANTY OR REPRESENTATION EXPRESSED OR IMPLIED !S MADE WITH s s R!$PECT TO THE ACCURACY, COMPLETENESS OR USEFULNESS OF THIS INFOR-f MATioN. GENERAL ELECTRIC COMPANY ASSUMES NO RESPONSlalLITY FOR LIA- t'

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o March 19,.1976 O

'SIL No. 155 identified by a small sticker label affixed to the back end or side of each

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switch having a number less than 50 and two letters in the following series:

AJ DJ GJ KJ .

AK DK GK KK AL DL HH LH BJ EJ HJ LJ BK EK HK LK BL EL JH MH CJ FJ JJ MJ CK FK JK MK CL GH KH Examples would be: "14GH" and "16HJ" Appendix A lists the results of a records search conducted by General Electric-Nuclear Energy Division of the known application of Class 1E SBM switches in operating BWRs, including the specific location of the SBM switches that are identifiable to the A through M series discussed above. The records review was limited to operating BWRs original equipment hardware as well as hardware

- in support plants afterofJune Field30, Disposition 1972. Instructions (FDIs) shipped to BWR operating  ;

I RECOMMENDED ACTION ( l General Electric recomends the following action: -

1.

Replace any SBM Control Switch currently installed in a BWR plant which is identified in the A through M series listed above and used in Class IE application as indicated in Appendix A.

2. ...-

Order SBM switch replacements by the Panel Parts List General Electric Part Number to assure that such replacements will be to their original configuration requirements. -

3.

For switches identifiable in the A through M series and having a number less than 50 as described above, and with applications other than Class IE, the cam followers can be inspected for cracks with an auxiliary light source of adequate intensity through the opening near the terminals of each switch deck. It ~

is advisable this inspection. to refrain from switch dissassembly for purposes of 4.

The switch application and its frequency of use as well,as the results of the visual inspection should determine if immediate ,

replacement would be in the best interest.

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March 19.1976 ' SIL No. 155 Contact your local GE service representative for additional information and for assistance in ordering replacement parts.

Prepared by: M.J. Sierra /L.A. Gonzalez Approved by: Issued by:

D.L. Lay n Manager D.L. L ton, Acting Manager Product rvice Perfo ance Analysis and Servi e Communications Product

Reference:

A71 - Plant Recommendations I

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APPENDfX A .

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LOCATTON AND DATE CODES OF GE TYPE SBM CONTROL

.l SWITCHES IN ESSENTIAL (CLASS IE) APPLICATIONS '

BWR PLANT PANEL QTY DEVICE LOCATION DRAWING # DATE CODE '.

p. Fitzpatrick 9-3 1 23A-S20 234A9327P002 14AJ 9-8 -

3 32B, 32E, 32F 248A9615P001 Please check

, No cert. avail-

! e able 9-21 32, 33, 41, 42

./-

9-3 2 234A9327P002 14AJ 9-75 1 9-075-000 235All27P002 '

14MH 9-75 2 15-MOV-102 248A9117P001 14JH 15-MOV-103 s

Peach Bottom II 9-4 2 16A-188 234A9329P003 14MH 9-41 16A-198 14LH 9-4A 1 32, 39 234A9327P002 Cert. dated 10/13/75.

No Date Code Could be KL gg Peach Bottom III 9-48 1 32, 39 >m 234A9327P002 Cert. dated 10/13/75.

No Date Code 3E g, p 9-4 Could be KL --

2 16A-188 234A9329P003 -

9-41 16A-198 14MH, 14LH Brunswick II (Carolina I) H12-P601 1 E51AS15 234A9330P002 14MH

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