ML20094Q762
| ML20094Q762 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 08/07/1984 |
| From: | Root R WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| GO1-84-0209, GO1-84-209, NUDOCS 8408200317 | |
| Download: ML20094Q762 (2) | |
Text
i ilECElVED tw Washington Public Power Supply System P.O. Box 968 3000GeorgeWashingtonWay Richland,WashinYton 99352iS34 <E 13 F411: 32 (509)372-5000 EEGION tilgr August 7, 1984 Responds to:
G01-84-0209 Response required by:
Mr. J.B. Martin Regional Administrat'or Nuclear Regulatory Commission Region V 1450 Maria, Lane, Suite 210 Walnut Creek, CA 94596
Subject:
NUCLEAR PROJECT NO. 1 DOCKET NO. 50-460 POTENTIALLY REPORTABLE CONDITION 10CFR50.55(e)
DEFECTIVE WELDS ON RADIATION MONITOR DISPLAY PANELS
Reference:
Telecon, C.R. Edwards, Supply System, to D.J. Willet, NRC, same subject, dated July 10, 1984.
In the reference, the Supply System informed your office of a potentially reportable deficiency under 10CFR50.55(e).
Attachment A provides a statement of the identified condition and a brief description of our planned actions to correct the identified deficiency.
Based on the current construction status at WNP-1, the Supply System will not be able to issue a final report at this time.
An update will be provided at construction restart.
If you have questions or desire further information, please advise.
R.W. Root, Jr.
WNP-1 Program Director (821)
RWR/GLW/cmh Attachment cc: TA Mangelsdorf, BPC 862 V Mani, UE&C 899 EC Haren, UE&C 895 NRC Document Control Desk, DC ORM 847 FDCC 899 8408200317 840807 PDRADOCK05000g
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I ATTACHMENT A DOCKET NOS. 50-460 POTENTIALLY REPORTABLE CONDITION PER 10CFR50.55(e)
DEFECTIVE WELDS ON RADIATION MONITOR DISPLAY PANELS Description of Deficiency The radiation monitoring equipment for WNP-1, supplied by Kaman Instrumentation, includes liquid and gaseous monitor assemblies which have display panel boxes mounted on top of the assembly. These display panel boxes, termed Local Indication and Control units (LIC), are bolted to the monitor skid. Seismic tests and analysis performed by Kaman indicates a potential safety hazzard exists unless corrected.
The failure mode is mechanical.
Four studs are spot welded onto the LIC and bolt through the monitor skid.
Kaman has found that, on some LIC's, the studs have insufficient spot welds to prevent the LIC from becoming a missile during a seismic event.
Analysis of Safety Implication In addition to the resultant loss of signal information from the monitor affected, the missile generated has the potential of causing a break in the sample lines to the monitor. The potential result would be a release of radioactive fluid or gases.
Cause of Deficiency The insufficient spot welds on some LIC's appears to have resulted from welding error during manufacture.
Corrective Action Kaman is preparing a test and retrofit procedure and parts kit for corrective action.
The test consists of a torque test on all the existing studs.
If they pass, no further action will be taken. The studs which fail will be replaced with a new bolt assembly.
The Supply System has 37 monitors with the potential of having defective stud welds.
Bechtel has issued a BNCR (1-BNCR-121-04) for each of these monitors.
The corrective action will be deferred until the restart of construction activities.
Action to Prevent Recurrence If additional monitors of these types are purchased, the specification will be modified to include the specific test for this condition to be performed at the Vendor's facility when spot welds are used.
Otherwise no further actions ' are necessary.