ML20083L890

Final Deficiency & Part 21 Rept SDR 83-06 Re Anchor/Darling Check Valves.Initially Reported on 830323.Arrangements Currently Underway to Correct,Repair or Rework Eight Valves at Each Site.Item Reported Per Part 21 by Vendor on 830331

ML20083L890
Person / Time
Site:	Wolf Creek, Callaway, 05000000
Issue date:	04/20/1983
From:	Seiken S STANDARDIZED NUCLEAR UNIT POWER PLANT SYSTEM
To:	Jay Collins, James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III), NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
REF-PT21-84-191-000 PT21-84-191, PT21-84-191-000, SDR-83-06, SDR-83-6, SLNRC-83-020, SLNRC-83-20, NUDOCS 8404170395
Download: ML20083L890 (2)

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SNUPPS Stenderdised Nale.+ Unit Power Plant System 5 Choke Cherry Mood Rocknile, Meryland 20560 1301) 56M010 April 20,1983 SLNRC 83-020 FILE: 0491.10.2 SUBJ: Final Report: Failure to Close, Anchor / Darling Check Valves (SDR 83-06)

Mr. James G. Keppler Administrator, Region III 3 (_M @ ( M !l N i h b

U.S. Nuclear Regulatory Commission s' 799 Roosevelt Road  ; NRP51983 Glen Ellyn, Illinois 60137

[ h Mr. John T. Collins Administrator, Region IV U.S. Nuclear Regulatory Conunission )

Suite 1000, Parkway Central Plaza Arlington, Texas 76012 Docket Nos. STN 50-482 and STN 50-483 Gentlemen:

On March 23, 1983, NRC Region III and Region IV representatives were informed by SNUPPS Staff (S. Seiken, R. White) of a deficiency in Callaway and Wolf Creek check valves manufactured by Anchor / Darling. During the March 23 notifications it was explained that check valves in the discharge lines of two of the four component cooling water pumps at the Callaway site had failed to close during startup testing of the pumps.

It was also reported that preliminary information indicated a design or materiel defect may have led to the failures, and that there were four check valves of the same design at each of the two SNUPPS sites (Valves '

EG-V003,-V007,-V012,and-V016). On the basis of a preliminary engineer-ing assessment, it appeared that, had this deficiency gone uncorrected, failure of these valves could occur under certain conditions and could result in any or all of the following: cavitation damage to component cooling water pumps; a significant reduction in component cooling water with a resultant loss of adequate cooling to several safety-related pumps, including safety injection and residual heat removal pumps; and reverse flow through the parallel-connected component cooling water pump, resulting in uncertain starting capability on demand. .

Since the March 23 notifications it has been confirmed that the valve failures were caused by improper design, specifically the use of incompat-ible materials of similar hardness for the valve seat hinge pins and bushings. This incompatibility resulted in pin / bushing galling and D\g eventual freezing of the valve seat in the open position. This valve deficiency was also reported to the NRC by Anchor / Darling on March 31, 1983, pursuant to 10CFR21 reporting require g ty. ao cricInL g41703958304 s r c.run.aarl N

f, SLNRC 83- 020 Page Two A review of materials -equirements has been conducted for all check valves in safety-related service, covering valves furnished by all SNUPPS vendors including Anchor / Darling. It has been determined that, in addition to the four component cooling water pump discharge check valves, a similar hinge pin / bushing materials incompatibility exists in four other Anchor / Darling check valves installed in the feedwater systems at each SNUPPS site (Valves AE-V120, -V121, -V122, and -V123).

Arrangements are currently underway to correct, repair or rework the eight check valves at each site as follows:

1. Callaway - As a temporary fix, replacement hinge pins and Type 416 heat treated bushings will be installed in the two damaged 20" com-ponent cooling water pump discharge check valves. This temporary fix will enable system and component testing to continue until a permanent fix is completed.

2. Callaway and Wolf Creek - As a permanent fix, replacement Stellite 6 bushings, and replacement hinge pins if required, will be installed in each of the eight affected valves at Callaway and at Wolf Creek.

Shipment of the replacement Stellite 6 bushings by Anchor / Darling is not anticipated before May, 1983. Installation of the replacement bushings will be complete prior to final turnover of the com-ponent cooling water and feedwater systems at each site. These valve repairs and bushing replacements will be accomplished according to established construction and rework practices and procedures at Callaway and Wolf Creek.

This report should be considered the final report concerning the Anchor / Darling check valve deficiency. The NRC will be informed should there be any new developments.

Very truly yours, w

S. J. Seiken Manager, Quality Assurance cc: D. T. McPhee, KCPL G. L. Koester, KGE D. F. Schnell, UE H. W. Roberds, USNRC/WC J. H. Neisler, USNRC/ Cal H. M. Wescott, USNRC Region III Richard DeYoung, Director I&E Record