ML20135E823
| ML20135E823 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 09/03/1985 |
| From: | Tamlyn T COMMONWEALTH EDISON CO. |
| To: | Case E NRC |
| References | |
| TKT-85-47, NUDOCS 8509170045 | |
| Download: ML20135E823 (2) | |
Text
4 O Commonwealth Edison Quad Cities Nuclear Power Station 22710 206 Avenue North Cordova, lilinois 61242 Telephone 309/654-224*
TKT-85-47 September 3, 1985 Mr. Edson G. Case, Deputy Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Case:
Enclosed please find a listing of those changes, tests, and experi-ments completed during the month of August, 1985, for Quad-Cities Station Units 1 and 2 DPR-29 and DPR-30.
A summary of the safety evaluation is being reported in compliance with 10 CFR 50.59.
Thirty-nine copies are provided for your use.
Respectfully, COMMONWEALTH EDISON COMPANY QUAD-CITIES NUCLEAR POWER STATION T. K. Tamlyn Services Superintendent bb Enclosure ec:
J. Wojnarowski 8509170045 850903 PDR ADOCK 05000254 i
R PDR
,\\
m Modification M-4-2-85-20 Description
.This modification was to drill a quarter-inch (1/4) deep hole in the Feedwater Check Valve 2-220-62B hinge pin in order to accomodate a deeper set screw penetration.
The modification was initiated due to one hinge pin in the Feedwater Check Valve found to be missing.
A quarter-inch deep (1/4) hole was drilled in the neck of-the hinge pin, thus allowing the set screw to be turned into the hinge pin an additional quarter-inch.
This provides a more secure set screw / hinge pin
- attachment.
Evaluation-The quarter-inch hole in the hinge pin does not significantly alter the mechanical strength of the pin. The manufacturer of the pin has drilled a hole in the pin at the same location for newer (third generation) pins.
By providing a more secure set screw / hinge pin attachment, the possibility of a failure of this type has been reduced.
.