ML20116C463
| ML20116C463 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 10/30/1992 |
| From: | William Cahill, Woodlan D TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| CP-92-08, CP-92-8, TXX-92517, NUDOCS 9211040049 | |
| Download: ML20116C463 (2) | |
Text
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i W-Log # TXX 92517 79 file # 10110 CP 92 08 l
,__r Ref. # 10CFR50.55(e) illFLECTRIC October 30, 1992 u num J. r.hin. Jr.
u..., n a r.na..a U. S. lhiclear Regulatory Commission Attn: Document Control Desk Washington, DC 200$$
SUBJECT:
C0HANCHE PEAL STEAM ELECTRIC SI ATION (CPSES)
DOCLE1 NUS. 50 445 AND 50 446 EDG AUT 2,..
LUV O!L PUHP SUC110N CHECK VALVE SDAR Cf N %
9 % "POR1 )
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TV Liect 'r 1m y ec 1XX-92378 from W. J. Cahill, Jr.
t o NRC detta a a 21, 1992 Gen t l eme n :
On July 22, 1992, via facsimile, TV Electric notified the NRC of a reportable defect in the CPSES Unit 2 Train
- B* diesel generator auxiliary lube oil pump suction swing check valve (f oot valve) located in the lobe oil sump (ref erenced above).
The last report, logged as TXX+92378, dated August 21, 1992, stated that the determination of root cause and corrective action to prevent recurrence was still ongoing.
This repor*. provides that final determination.
There are two cont ributing f actors to ;.he valve f ailure.
The valve disc hinge bolts were too long, causing force to be applied to the valve casting in the area of the damage.
A project design change document has been initiated to require that the flapper hinge bolts be replaced and shortened as necessary in all of these valves to prevent damage, lhis will be completed prior to Unit 2 fuel load.
The other contributing f actor was a potential casting flaw in the valve.
All nine valves in the warehouse have been magnetic particle examined. Two valves were scrapped because of indications unrelated to this deficiency.
The other seven were accepted.
Two of the four valves installed in Unit 2 have been magnetic particle examined, accepted and reinstalled.
The design change document noted above also requires magnetic particle examination of the remaining two Unit 2 valves, This will be completed prior to Unit 2 fuel load.
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'1XX 92517 Page 7 of P As stated in the above ref erence, this def ect is applicable to CPSES Unit 1 and the foot valves currently installed in Unit 1 will be inagnetic particle examined during the second ref ueling outage of CPSCS Unit 1.
Additionally, the flapper hinge bolts will be inspected f or proper length and appropriate action talen as necessary.
Sincerely, 1
William J. Cahill, Jr.
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By:
i D. R. Woodlan l
Docket Licensing Manager
-l MCP/ds c - Mr. J. L. Hilboan, Pegion !V Resident inspectors CPSES (2)
Hr. B. L. Holian, NRR
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