ML20195J201

Final Deficiency Rept CP-87-19 Re Ambient Temp Effects on MSIV Actuators.Initially Reported on 870711.Actuators Returned to Rockwell Intl for Repairs.Valves Will Be Reinstalled & Corrective Actions Completed by 890101

ML20195J201
Person / Time
Site:	Comanche Peak
Issue date:	01/18/1988
From:	Counsil W TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
CP-87-19, TXX-88104, NUDOCS 8801260435
Download: ML20195J201 (2)

Text

. - _ _

m ,==m -

EE r_,

Log # TXX-88104

.""' File # 10110

= = 910.3 illELECTRIC

" # **""00'00('I I,I,," Sd%,1, January 18, 1988' U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CP5ES)

DOCKET NOS. 50-445 AND 50-446 AMBIENT TEMPERATURE EFFECTS ON HSIV ACTUATORS SDAR: CP-87-19 (FINAL REPORT)

Gentlemen:

On June 11, 1987, we verbally notified your Mr. R. F. Warnick of a deficiency involving the ambient temperature effects on MSiv actuators. After further evaluation we have determined that this deficiency is reportable pursuant to 10CFR50.55(e). Our last interim report was logged TXX-88083, dated January 11, 1988. The required information follows.

DESCRIPTION TU Electric was notified by the manufacturer (kockvoll International) that the thermal compensating accumulator on the valve actuator attached to the Main Steam Isolation Valves (MSIV) may not function in accordance with the CPSES procurement specification. The specification requires the actuator to function correctly through an ambient temperature swing of 80 degrees F. Test results acquired by Rockwell indicated the greatest possible ambient swing which will not impair the function of the actuator is 34 degrees F.

In our interim report logged TXX-6557, dated July 10, 1987, we described our evaluation to determine 1f the temperature transient could be limited to 55 degrees F, which would support the accumulators. This evaluation has been completed, and we have determined that the temperature transient cannot be limited to 55 degrees F. Therefore, the accumulators supplied by Rockwell International are not adequate for design conditions. As a result of recent field experience and subsequent testing by the supplier, and our own evaluation, this deficiency is limited to the Rockwell Main Steam Isolation Valves with A-180 actuators.

SAFETY IMPLICATIONS This item represents a failure by the vendor to supply the specified component. Per vendor analysis the supplied component cannot withstand the temperature conditions specified in the purchase specification. Damage to the accumulators caused by design condition could prevent MSiv closure, p gp2gb598o118-osoogggs S

_,, ,,,,,,,, ,, _ 7_ , j g

TXX-88104 January 18, 1988 Page 2 of 2 CORRECTIVE ACTION Correction of this deficiency will require the subject actuators to be returned to Rockwell International for repairs. To minimize the impact on construction and testing schedules, the Unit 2 actuators will be sent to the vendor for repair and returned for use in Unit 1. Then the Unit 1 actuators will be sent for repair and returned for use on Unit 2. All valves will be returned to CPSES no later than June 1, 1988. The valves will be re-installed and all corrective actions completed no later than June 1, 1988 and January 1, 1989 for Units 1 & 2 respectively.

Very truly yours, f//&A W. G. Counsil MCP/grr

c - Mr. R. D. Martin, Region IV i Resident Inspectors, CPSES (3) l l

l J