TXX-4043, Interim Deficiency Rept Re Borg-Warner Check Valves.Valves of Similar Design Disassembled,Inspected & Repaired.Due to Number of Affected Valves Involved,Corrective Actions Will Not Be Completed Prior to Fuel Load
| ML20077Q908 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 09/07/1983 |
| From: | Gary R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | Madsen G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, TXX-4043, NUDOCS 8309160218 | |
| Download: ML20077Q908 (2) | |
Text
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9 Oe Q TENAS UTILITIES GENERATING COMinNY m,,,iin s w,w.... s u. m.,, w m., :.
September 7, 1983 R. J. GARY "l=l',71';",r!!.~'
TXX-4043 Mr. G. L. Madsen, Chief Reactor Project Branch 1 U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement 611 Ryan Plaza Drive, Suite 1000 Docket Nos.:
50-445 Arlington, TX 76012 50-446 p
{z COMANCIIE PEAK STEAM ELECTRIC STATICN rr BORG-WARNER CHECK VALVES hI
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QA FILE: CP-83-01 Rev. 1, SDAR-119
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FILE No.:
10110 l
Dear Mr. Madsen.
j In accordance with 10CFR50.55(e), we are submitting the enclosed report of actions taken to correct a deficiency regarding disengaged parts of certain check valves.
Supporting documentation is available at the CPSES site for your Inspector's review.
Very truly yours,
/$
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/g R. J. Gary RJG:ln cc: NRC Region IV - (0 + 1 copy)
Director, Inspection & Enforcement (15 copies)
U. S. Nuclear Regulatory Commission Washington, DC 20555 0309160218 830907 PDR ADOCK 05000445 PDR S
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- g TXX-4043 September 7, 1983 ATTACHMENT BORG-WARNER CHECK VALVES Although this deficiency involves the same valves identified in the original SDAR, CP-83-01, the deficiencies are not similar in effect. However, since the Borg-Warner valves are already included in the scope of the original SDAR, the following is a revised response addressing all known Borg-Werner valve concerns.
DESCRIPTION OF THE DEFICIENCY During disassembly of the containment spray heat exchanger, disengaged parts of the upstream check valves were discovered. The condition was reported per a site nonconformance report.
The valve disc is connected to the operating arm by a stud welded to the disc. The disengaged parts resulted from a broken tack weld securing the stud.
Further inspection of two (2) similar valves indicated typical faulted tack welds. A third valve was observed to have the stud securely fastened by a fillet weld. The supplier (Borg-Warner) has advised fillet welds are currently standard design.
In order to assure implementation of the current " standard design", site engineering inspected similar valves provided by the supplier. Additional discrepancies observed were:
- 1) linear indications in the swing arm which connects the valve disc to the valve body; and 2) base metal degradation under the fillet weld which secures the valve disc stop to the valve bonnet.
The additional discrepancies were identified in various valves installed throughout the plant design.
Site nonconformances have been issued.
SAFETY ANALYSIS Due to the varied applications of the valves, the ability of the operator to safely mitigate the consequence of an accident could not be assured.
CORRECTIVE ACTION All valves provided by the supplier of similar design will be disassembled, inspected, and repaired. Valves found to require repair will be identified by site nonconformance reports. Due to t he number of affected valves involved in testing and construction efforts, corrective actions will be complete prior to fuel load.
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