ML19351E667
| ML19351E667 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 11/06/1980 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Oprea G HOUSTON LIGHTING & POWER CO. |
| References | |
| NUDOCS 8012100615 | |
| Download: ML19351E667 (1) | |
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,,f UNITED STATES f f 7,,, e g NUCLEAR REGULATORY COMMISSION I
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. -j REGION IV
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611 RYAN PLAZA DRIVE. SUITE 1000 ARLINGTON, TEXAS 76011 November 6, 1980
.g In Reply Refer To:
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Docket Nos. 50-498/IE Bulletin No. 80-21 50-499/IE Bulletin No. 80-21 i
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Houston Lighting & Power Company ATTN: Mr. G. W.* 0prea, Jr.
Executive Vice President Post Office Box 1700 Houston, Texas 77001 Gentlemen:
The enclosed IE Bulletin No. 80-21 requires your action with regara to your power reactor facilities holding an operating license or a construction pennit.
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Should you have questions concerning this bulletin or the actions required of you, please contact this office.
Sincerely, f
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Karl V. Seyfrit -
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Director
Enclosures:
1.
List of Recently issued IE Bulletins 80121o oW5 O
o SSINS No.:
6820 Accession No.:
8008220246 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE BULLETIN NO. 80-21 November 6, 1980 Page 1 of 3 VALVE Y0KES SUPPLIED BY MALCOLM FOUNDRY COMPANY, INC.
Description of Circumstances:
On June 17, 1980, Pennsylvania Power and Light Company notified IE Region I that cracks had been discovered in the yokes of a number of valves in the residual heat removal (RHR) system at their Susquehanna Steam Electric Station.
The potential for common-mode failure of the yokes on several valve in redundant, safety-related trains of the RHR system constitutes a failure mode whereby all RHR functions could be simultaneously lost.
Specifically, the cracks were located in the radii at the yoke mounting flange-to yoke vertical section interface.
An analysis and evaluation of the most severely cracked valve yoke was performed by the valve manufacturer, Anchor Darling Valve Company.
They concluded that the cracking was not due to casting defects, but rather was due to the yoke material not having the proper mechanical properties.
Purchased as ASTM A-216, Grade WCB material, the actual valve yoke material had tensile and yield strengths below the minimum values listed in the ASTM material specification.
The cracked valve yokes were all cast by Malcolm Foundry Company, Inc., of Newark, New Jersey.
The foundry is no longer in business.
Anchor Darling has begun a program of verifying the tensile strengths of the other valve yokes cast by Malcolm and used on Anchor Darling valves at Susquehanna.
To date, approximately half of the valve yokes have been tested.
Of those tested, over 25 percent of the valve yokes have revealed B'inell hard-ness values significantly below the appropriate value obtained fror, the approxi-mate relationship of Crinell hardness to tensile strength included in ASTM Specification A-370.
These additional "alve yokes are on a wide range of valve sizes and are from a number of different purchase orders placed with Malcolm over a period of at least ten months during 1974 and 1975.
Thus, it appears that the problem is not isob ted to one heat of material or to one short time period.
Anchor Darling is.tends to replace the defective valve yokes at Susquehanna and to begin a testing program at other nuclear power plants under construction where valves with valve yokes cast by Malcolm have been provided.
Since Malcolm Foundry Company, Inc., is no longer in business, the NRC staff cannot determine directly if Malcolm has provided valve parts to other valve manufacturers for use in nuclear power plants.
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o IEB 80-21 November 6, 1980 Page 2 of 3 Actions To Be faken by Addressees:
For all power reactcr licensees or holders of construction permits the following actions are required:
1.
Determine if any of the active valves in use or planned for use in safety-related systems at your facility have valve parts cast by Malcolm Foundry Company, Inc.
If no valves are identified as having potentially faulty material, indicate that this is the case and ignore the remaining questions.
2.
Licensees having active safety-related valves with potentially faulty material shall immadiately visually inspect for cracks all normally accessible valve parts (i.e., those which can be inspected during reactor operation).
3.
Licensees or permit holders having active safety-related valves with potentially faulty material shall identify the manufacturer (s) of these valves and either:
a.
Verify that all valve parts cast by Malcolm have mechanical properties in accordance with the ASTM material specification; if such is not the case, then comply wita either b. or c. be~!ow, b.
Replace the defective materials and/or valves, Identify any other corrective actions that may be exercised and the c.
basis for such actions.
For plants with an operating license, the results of your initial determination (item 1), visual inspection results (item 2), a list of affected valve manu-facturers, your planned action (item 3), and the schedule for accomplishing this action shall be reported within thirty days of the date of this bulletin to the Director of the appropriate NRC Regional Office with a copy sent to the NRC Office of Inspection and Enforcement, Division of Reactor Construction Inspection, Washington, DC 20555.
e For plants with a construction permit, the results of your initial determination (item 1), a list of affected valve manufacturer (s), your planned action (item
- 3) and the schedule for accomplishing this action shall be reported within sixty days of the date of this bulletin to the Director of the appropriate NRC Regional Office with a copy sent to the NRC Office of Inspection and Enforcement, Division e# Reactor Construction Inspection, Washington, DC 20555.
Compliance with this bulletin by the licensees does not relieve the affected valve manufacturers from the reporting requirements of 10 CFR Part 21.
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IE8 80-21 i'
November 6, 1980 Page 3 of 3 If you desire additional information regarding this matter, please contact the l-appropriate IE Regional Office.
Approved by GAO, B180225 (R0072); clearance expires November 30, 1980.
Approval was given under a blanket clearance specifically for identified generic problems.
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IE Bulletin No. 80-21 November 6, 1980 f.
ENTLY ISSUED IE BULLETINS Bulletin Suoject Date Issued Issued To No.
80-19 Failures of Mercury-Wetted 7/31/80 All nuclear power Matrix Relays in Reactor facilities having Protective Systems of either an Operating Operating Nuclear Power License (OL) or a Plants Designed by Combus-Construction Permit (CP) tion Engineering 80-20 Failures of Westinghouse 7/31/80 To each nuclear Type W-2 Spring Return power facility in to Neutral Control your region having Switches an Operating License (0L) or a Construction Permit (CP)
Sup. 3 Failure of Control Rods 8/22/80 All BWR power reactor to 80-17 to Insert Ouring a Scram facilities holding at a BWR Operating Licenses (0Ls) or Construction Permits (cps) 79-26 Borer. Loss from BWR 8/29/80 All BWR power facilities Rev. 1 con col blades with an Operating License (0L) 80-22 Automation Industries, 9/11/80 All radiography Model 200-520-008 sealed licensees sources connectors Sup. 2 Environmental Qualifica-9/30/80 All power reactor to 79-018 tion of Class IE facilities with an Equipment Operating License (0L)_
or Construction Permit (CP)
Sup. 3 Environmental Qualifica-10/24/80 All power reactor to 79-108 tion of Class IE facilities with an Equipment Operating License (0L) or Construction Permit (CP)
Enclosure
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