ML20093K780

Responds to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power Operated Gate Valves

ML20093K780
Person / Time
Site:	Comanche Peak
Issue date:	10/16/1995
From:	Terry C TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-95-07, GL-95-7, TXX-95263, NUDOCS 9510240384
Download: ML20093K780 (5)

Text

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Log # TXX 95263

. - = = = = File # 10035 i'* P """' Ref. # :10CFR50.54(f)

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GL 95 07

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October 16, 1995 nevwraae -

U. 'S. Nuclear Regulatory Commission Attn.: Document Control Desk Washington, DC 20555 0001

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)

DOCKET N05. 50 445 AND 50-446 UNITS 1 AND 2 RESPONSE TO GENERIC LETTER 95 07, " PRESSURE LOCKING AND THERHAL BINDING 0F SAFETY RELATED POWER OPERATED GATE VALVES" REF: 1) Generic Letter 95 07, " Pressure Locking and Thermal Binding of Safety Related Power Operated Gate Valves," dated August 17, 1995 Gentlemen:

On August 17, 1995, the NRC issued Generic Letter 95 07, " Pressure Locking and Thermal Binding of Safety Related Power Operated Gate Valves" (Reference 1).

Pursuant to Section 182a of the Atomic Energy Act of 1954, as amended, and 10 CFR 50.54(f). TU Electric is submitting a response under affirmation l (Attachment 1) to the requested information and requested actions as stated  !

in Reference 1. l NRC GL 95 07 Reauested Actions:

Within 90. days of the date of this generic letter, each addressee of this generic letter is requested to perform and complete the following actions:

1. Perform a screening evaluation of the operational configurations of all safety related power operated (i.e., motor operated, air operated, and hydraulically operated) gate valves to identify those valves that  ;

are potentially susceptible to pressure locking or thermal binding:  !

and

2. Document a basis for the operability of the potentially susceptible valves or, where operability cannot be supported, take action in accordance with individual plant Technical Specifications.

Within 180 days of the date of this generic letter, each addressee of this

. generic letter is requested to implement and complete the guidance provided  ;

in Attachment 1 to perform the following actions: 1

1. Evaluate the operational ' configurations of safety related power operated (i.e., motor ope, rated, air operated, and hydraulically 9510240394 951016 6 PDR ADOCK 05000445 ,

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TXX 95263

.Page 2 of 4 L l operated) gate valves in its plant to identify valves that are  ;

susceptible to pressure locking or. thermal binding; l

2. Perform further analyses as appropriate, and take needed corrective l

actions (or justify longer schedules), to ensure that the: susceptible l valves ' identified in-1 are capable of performing their intended safety i function (s) under all modes of plant operation, including test configuration.

l NRC GL 95-07 Reauested Information:

~All addressees, including those who have already satisfactorily addressed I pressure: locking and thermal binding for MOVs by implementing the guidance

~

l in Supplement 6 to GL 89 10 (or equivalent industry methods), are requested ,!

to provide a summary description of the following: _l 1

l '. The susceptibility evaluation of operational configurations performed )

in. response to (or. consistent with) 180 day Requested Action 1, and-the further analyses performed in response to (or consistent with)

.180 day Requested Action 2 including the bases or criteria' for determining that valves are or are not susceptible to pressure locking or thermal binding:

2. The results of the susceptibility evaluation and the further analyses referred to in 1 above, including a listing of the susceptible valves identified; i i

3. The corrective actions, or other dispositioning, for the valves identified as susceptible to pressure locking or thermal binding,

, including: (a) equipment or procedural modifications completed and

. planned (including the completion schedule for such actions); and (b) justification for any determination that particular safety-related

)ower operated gate valves susceptible to pressure locking or thermal 3

>1nding are acceptable as is.

f NRC GL 95 07 Reauired Resoonse:

l All addressees are required to submit the following written response to this generic letter:

1. Within 60 days from the date of this generic letter, a written 4 response indicating whether or not the addressee will implement the action (s) requested above. If the addressee intends to implement the o requested action (s), provide a schedule for completing implementation, If an addressee chooses not to take the requested action (s), provide a description of any proposed alternative course of action, the schedule for.' completing the alternative course of action (if applicable). and

-the safety basis for determining the acceptability of the planned alternative course of action:

2. Within 180 days.from the date of this generic letter, a written response to the ~1nformation request specified above.

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TXX 95263' 4 Page 3 of 4 TU Electric resnonse:

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, 1) .The Westinghouse Owners Group;(WOG) has developed a program to assist i '

.in~ addressing the. requirements of GL 95 07. The aforementioned

' program is establishing a set of criteria, which can be applied in the screening and evaluation of gate valves for the pressure locking and thermal ~ binding phenomena. ~This' set of screening criteria is being-

-defined to identify valves potentially susceptible to pressure. locking and: thermal binding.:taking into account both component and system

. considerations. Criteria and methodology are also being developed .to assist in the evaluation of susceptibility of each valve determined to be potentially susceptible to pressure locking and thermal binding.

' Once the criteria have been established. TV Electric will- apply the

/ criteria to Comanche Peak Steam Electric Station's (Units 1 and 2) population of safety related, power operated gate valves. As

~ susceptible valves are identified, the evaluation criteria and methodology will be used to determine the need for additional analysis and/or valve modifications. '

TU Electric intends to implement the actions requested in GL 95 07,~

and has commenced the initial screening evaluations. The WOG Task Team has established an aggressive schedule for the criteria development for valves susceptible; to pressure locking and thermal Lbinding,'and this criteria will.be reviewed and utilized as it becomes available. . If at any time the susceptibility evaluation identifies a valve as being susceptible to either pressure locking or thermal binding, and corrective actions have not been taken, an operability assessment will be performed and a justification for continued operations developed. If operability cannot be demonstrated, the applicable Technical Specifications actions will be followed.

2) TU Electric will comply with all actions and responses specified in the 180 day required response. These include completion and documentstion of the following:

. Screening criteria.

• List of susceptible valves.

• Description of evaluations.

. Susceptibil_ity evaluation results.

Corrective actions taken or scheduled.

= Justifications for continued operations, as needed.

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ci TXX 95263 Page 4 of.~4

-These actions will.be completed and the responses provided to the NRC within 180 days-of the date of Generic Letter 95-07. ,

l If you have any questions, please contact Obaid Bhatty at (817) 897 5839. l

. Sinc'[y, C. L. Ter l

l 1

OB/ob . l Attachment i 1

c- Mr. L. J. Callan. Region IV )

Resident Inspectors, CPSES Mr. T. J.-Polich, NRR

Attachm'ent 1 to TXX 95263 l Page 1 of 1 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION 1

In the Matter of )

)

Texas Utilities Electric Company ) Docket Nos. 50 445

) and 50 446 (Comanche Peak Steam Electric )

Station, Units 1 & 2) )

AFFIDAVIT Charles L. Terry being duly sworn, hereby deposes and says that he is the Group Vice President, Nuclear Production of TV Electric, the licensee herein: that he is duly authorized to sign and file with the Nuclear Regulatory Commission this Response to Generic Letter 95 07, Pressure  ;

Locking and Thermal Binding of Safety Related Power Operated Gate Valves";

that he is familiar with the content thereof: and that the matters set forth therein are true and correct to the best of his knowledge, information and belief. i l

NA ^ '

Charles L. Tdrry Group Vice Preside <

Nuclear Production STATE OF TEXAS )

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COUNTY OF ad ) )

Subscribed and sworn to before me, on this /4// day of [#fMA, 1995.

l SUSAN C.GRAVA1T l 0,A ?n? NEE lE?uS Commissim E@s m-97

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