ML20024C301
| ML20024C301 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 06/29/1983 |
| From: | De Lorenzo R WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Sternberg D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| REF-PT21-83 10CFR-050.55E, 10CFR-50.55E, GO1-83-343, NUDOCS 8307120499 | |
| Download: ML20024C301 (2) | |
Text
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EECElygg Washington Public Power Supply System P.O. Box 968 3000 GeorgeWashingtonWay Richland, Washington 993g (509) 372-5000 bl ' S p;j I2' 3 7 June 29,1983 G01-83-343 Nuclear Regulatory Commission 46/0,y,,g Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596 Attention:
D.M. Sternberg, Chief Reactor Projects Branch No. 1
Subject:
NUCLEAR PROJECT NOS. 1 & 4 DOCKET NOS. 50-460 AND 50-513 P0TENTIALLY REPORTABLE CONDITION 10CFR50.55(e)
EMERGENCY DIESEL GENERATOR STARTING AIR VALVE ASSEMBLY
Reference:
A) Telecon CR Edwards, Supply System to PP Narbut; dated 6/18/82.
B) G01-82-0436, same subject, dated July 16, 1982.
In reference A) the Supply Sysic.. informed your office of a potentially reportable condition under the provisions of 10CFR50.55(e) and Reference B was an interim report on the subject condition.
Attachment A has been updated to identify that the design change has been documented but is not yet implemented.
As described in the attachment, the Supply System will take the most conserva-tive approach and replace the capscrews. As a result, the reportability status of this potential defect will remain indeterminate.
Due to the current construction delay on WNP-1, the Supply System will not be able to implement the required hardware modifications and issue a final report.
As a result the Supply System will provide the next interim report at construction restart.
If you have any questions or desire further information, please advise.
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R.A. De Lorenzo WNP-1 Program Director (821)
RAD /LC0/cmh Attachment cc: CR Bryant, BPA (399)
TA Mangelsdorf, Bechtel (861)
V Mani, UE&C (897)
V Stello, Director of Inspection, NRC FDCC (899)
ORM (847)
A. Toth, NRC F307120499 830629 PDR ADOCK 05000460 pgll S
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WNP-1/4 DOCKET NOS. 50-460 & 50-513 REPORTABLE CONDITION PER 10CFR50.55(e)
EERGENCY DIESEL GENERATOR STARTING AIR VALVE ASSEMBLY BACKG0VND The Supply System purchased Emergency Diesel Generators, two per plant, from Transamerica Delaval.
Transamerica Delaval has reported under the requirements of 10CFR Part 21, a deficiency associated with the starting air valve assembly, which is described in detail under " Description of the Deficiency".
The starting air valve assembly was manufcctured and installed in the cylinder head by Transamerica Delaval.
Following receipt of the 10CFR Part 21 notification from Transamerica Delaval, Supply System Contract 53, it was determined that this deficiency was potentially reportable under the requirements of 10CFR50.55(e).
DESCRIPTION OF THE DEFICIENCY The design deficiency is related to the length of the capscrew which holds the l
starting air valve assembly in the cylinder head.
If all dimension tole-ances are stacked in one direction, the installed clearance is less than desirable.
SAFETY IMPLICATIONS If the capscrew bottoms out in the tapped hole in the cylinder head before the assembly is properly seated, the torque wrench reading would be misleading and the assembly could fail.
CORRECTIVE ACTION Transamerica Delaval has revised the design configuration to specify capscrews 2-3/4" long rather than 3" long.
A 1" shorter capscrew still gives adequate thread engagement and eliminates any possibility that the capscrew will bottom out in the tapped hole.
For our Emergency Diesel Generators the 3" capscrews will all be removed and replaced with the 2-3/4" capscrews.
This change will be accomplished at the site through a field change (QFPCP 01Q25231).
Based on the current WNP-1 construction delay the procurement and installation of the shorter capscrews will not take place until after construction is l
resumed.
Tracking of the deficiency and correction of the WNP-4 equipment has been assured by generation of a nonconformance report against the hardware (4-BNCR-53-02).
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