ML20138M575
| ML20138M575 | |
| Person / Time | |
|---|---|
| Site: | Perry  |
| Issue date: | 12/13/1985 |
| From: | Edelman M CLEVELAND ELECTRIC ILLUMINATING CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| PY-CEI-OIE-0151, PY-CEI-OIE-151, RDC-119(84), NUDOCS 8512230039 | |
| Download: ML20138M575 (3) | |
Text
THE CLEVELAND ELECTRIC ILLUMIN ATING COMP ANY P.O. BOX 5000 - CLEVELAND. OHIO 44101 - TELEPHONE (216) 622-9800 - ILLUMINATING BLDG.
- 55 PUBUCSOUARE Serving The Best Location in the Nation MURRAY R. EDELMAN q
VICE PRESIDENT NUCLEAR
\\
December 13, 1985 PY-CEI/0IE 0151 L Mr. James G. Keppler Regional Administrator. Region III Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137 RE: Perry Nuclear Power Plant Docket Nos. 50-440; 50-441 Dresser Industries Diaphragm Seal Globe Valves [RDC 119(84)]
Dear Mr. Keppler:
This letter is the final report pursuant to 10CFR50.55(e) concerning Dresser Industries diaphragm seal globe valves. Dresser Figure 3050.
Mr. R. C. Knop of your office was first notified on October 29, 1984, by Mr. P. P. Martin of The Cleveland Electric Illuminating Company (CEI) that this problem was being evaluated per Deviation Analysis Report 212. The last report on this subject was submitted on May 31,1985 (PY-CEI/0IE 0055LQ).
Description of Deficiency During Unit 1 leak rate testing activities. Dresser diaphragm seal globe valves, Figure 3050, were found to be sticking closed or partially open.
It has be.n determined that the problem is caused by insufficient clearance between the disc cap and guide along with sharp edges on the disc cap. Any uneven force applied to the spring or diaphragm causes the disc cap to tilt, whereupon the sharp edges bind to the guide. This anomaly affects all sizes of Dresser Figure 3050 valves supplied to the Perry Nuclear Power Plant (PNPP).
Additionally, the spring force on the 1/4 inch and 1/2 inch valves is not sufficient to overcome disc / seat friction and diaphragm resistance.
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2 Mr. Jame] G. K::ppler D:;ccabar 13. 1985 PY-CEI/0IE 0151 L Analysis of Safety Implications
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The failure of a manual flow path valve to open could inadvertently isolate I
a system or component required for safe shutdown or, a stuck closed test valve could mask a leaking containment isolation valve. As the usual method for determining the position of a manusi valve via handwheel operation would not identify a stuck closed diaphragm valve this condition is considered reportable.
It should be noted that there are no Dresser Industries' diaphraga seal globe valves utilized in an active application at PNPP.
Corrective Action
'The program undertaken by CEI to correct the subject Dresser valves supplied to PNPP requires, as applicable, implementation of the following modifications for leak rate test valves and flow path valves For 3/4 inch and larger valves, sufficient chamfering of disc caps on the outside diameter to eliminate the possibility of binding even when severely tilted..
For 1/2 inch and smaller valves in system flow paths, disc cap chamfering, and elimination of diaphragm resistance by removing the flexible diaphragm center to-ensure that the spring opens the valve. The diaphragm is not a pressure retaining part and is not required to ensure pressure integrity.
The program also requires verification of modification adequacy during the preoperational testing phase.- To date, no failures of modified Unit i valves attributable to design deficiencies have been noted and modification of the last six subject valves will be completed by December 14. 1985.
A Periodic Test Instruction (PTI) has been developed to address those infre-quently operated, unmodified Figure 3050 Dresser Industries diaphragm seal globe valves required for safe start-up, shutdown or specific testing applications as listed in the PTI. This PTI requires operator verification of open valve position utilising methods other than handwheel operation.
Please call if you have any questions.
Sincerely, gj h Murray R. Edelman Vice President Nuclear Group MRE sab
s Mr. ' Jame] G. K:pplcr Decembar 13, 1985 PY-CEI/0IE 0151 L cet Mr. J. A. Grobe. USNRC Site Office SBB50 Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C.
20555 Records Center. SEE-IN Institute of Nuclear Power Operations 1100 Circle 75 Parkway. Suite 1500 Atlanta. Georgia 33039 Mr. T. E. Meyers. President Industrial Valve Operations Division Dresser Industries Incorporated P.O. Box 1430 Alexandria. LA 71301