ML20091D582

Responds to Request for Clarification of Relief Request V-1 Re Differences Between in-situ Testing & Shop Testing & Specific Advantages of One Method Over Another.Revised Relief Request V-1 Encl

ML20091D582
Person / Time
Site:	Comanche Peak
Issue date:	04/06/1992
From:	William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TXX-92174, NUDOCS 9204100280
Download: ML20091D582 (4)

Text

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";;kg J - d log # TXX-92174

= """" File // 10010 L _~ Ref . // 10CFR50.55a r._

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M/ ELECTRIC April 6, 1992 William J. Cahill, Jr.

Group Vice tresuret U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)

DOCKET ll05. 50-445 CID 50-446 ,

REQUEST FOR ADDITIONAL INFORMATION ON PRE LIMl fl ARY ISSUES AFFECTING THE DEVELOPMENT OF THE CDSES UNIT 2 INSERVICE TEST PLAN FOR PUMPS AND VALVES REF: 'l Electric Letter logged TXX-92040 f rom

.' 'liam J. Cahill Jr. to NRC, dated February 3, 1992 Gentlemen:

The purpose of this letter is to provide additional information on Relief Request V-1 that was included in the referenced letter on the CPSES Unit 2 Inservice Test (IST) Plan for Pumps and Valves. The relief request was discussed with the NRC Staff in a telecon on March 20, 1992.

It was roquested that Relief Request V-1 be clarified by explaining the differences between in-situ testing and shop testing and the specific advantages of one method over the other. We have revised the relief request -

to include this discussion in the attachment. The revisions are identified with a "bar" in the margin.

If +r are are any questions, please call Mr. Chris Jensen, et

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• 41 E i2-8826.

Sincerely,

/ /, '

William J. Cahill, Jr.

CEJ/gj c - Mr R. D. Martin. Region IV Resident insectors. CPSES (2)

Mr. T. A. Bergman, NRR Mr. B. E. Holian. NRR 9204100280 DR ADOCK92040-6 05000445 PDR 400 N. Olive Street LB. 81 De:las, Yexas 75201

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V' Attachment 'to TXX-92174-Page 1 of_.3.

I RELIEF REQUEST NO. V1  ;

-SYSTEM (See-VALVE = NUMBER) ,

VALVE.-NUMBER U.ain Steam 2MS-0021 2MS-0022 2MS-0023 2MS-0024 2MS-0025 2MS-0058 2MS+0059 2MS-0069 2MS-0061 2MS-0062

-2HS 0093 2MS-0094 2MS-0095 2MS-0096 2MS-0097 2MS-0129 2MS-0130 2ME n131 2MS-0132 2MS-0133 Reactor Coolant 2 8010A' 2-80iOB 2 8010C CATEGORY C CLASS- 2f(Main Steam), 1 (Reactor Coolant) 10ESCRIPTION . Main-Steam Safety Valves: Pressurizer Safety Valves TEST REQUIREMENT -0M.Part 1 para. 7.2, " Testing After Installation ,

Prior to Initial Electric Power Generation' (General requirement) 0M Part 1 para. 7.2.1.1 (Class 1 Safety Valves);

'Within 6 months prior cto initial fuel < loading, each 4

-valve shall have its set pressure verified. Set pressure verification shall be: determined by pressurizing the system up to +he valve set pressure

.and opening-the valve, or the . ve may be tested at or below normal system operating pressures with an assist de'vice.'~

-0M Part 1 . para.-7.2.2.1.a-(Main Steam Safety

-Valves); *After system heatup, but prior to initial reactor criticality, each valve shall be subjected to the following tests.

(1) Set pressure verification shall be determined-by

-pressurizing the system up to the valve' set. pressure and: opening the valve or the valve may be tested-at or below normal system operating-pressure-with an

• assist device.

42) Compliance with the Owner's seat tightness criteria'shall be verified."

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l Attachment to'TXX-92174-Page 2 of 3' BASIS FOR RELIEFL The primary intent of the subject Code paragraphs ~is to

- require testing of Class 1 (Pressurizer) and Main Steam Safety-Valves shortly before a Pressurized Pater Reactor

_ plant is initially started up, .This requirement is reasonable when one considers the safety significance of these valves and the fact that years may elapse between the manufacturer's shop test and the time the valves are

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first placed in service. However.'the Code also seems

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to imply that the required testing, for this specific instance only, should be done with the valves in-place.

While in-place testing may apparently offer a convenience in that valve removal and reinstallation is averted, removal of the valves from the system for testing (at a testing lab), can yield equally valid test results and offer soma distinct advantages.

In particular, valve maintenance and adjustment can be accomplished more easily in the testing lab environment.

For example, the Pressurizer and Main Steam Safety Valves are known to experience ; eat leakage after cycling. _After set pressure verification the valves of ten must be disassembled (while retaining spring compression) so that the disc insert and nozzle seating surfaces can be-lapped, if the set pressure verificatior, was performed in place, the subsequent seat leakage . repairs would entail- cooldown and depressurization of the Reactor Coolant -and. Main Steam Systems, Following valve repair and reassembly the systems would then. have to be heated back up and repressurized to conduct a valve seat leakage retest.

(Recali that OM Part 1 requires seat leakage testing to s- be done under tne same temperature conditions and using h

-the same fluid-media as for the set pressure verification.)

i c e, . - . . . -

ttacinent to TXX-92174 Page 3 of 3 Pressurizer and Main Steam Safety Valve testing and maintenance can be performed at a testing lab, on the other hand, and thereby eliminate the need to cycle the entire reuctor plant. The test lab f acilities allow the exact operating conditions (fluid media, temperature stability and ambient temperature) of the valves to be simulated for testing and provide easy access to the valves should any maintenance be required. Actual set presrure on steam can be verified at a testing lab without utilizing an assist device, The additional activities essociated with testing the valves at a lab such as valve removal, shipping and reinstallation can _

be accomplished safely by applying the procedural and quality controls normally required for such work. The valves are rigged, boxed and shipped in the vertical position and are receipt inspectea both at the testing lab and upon their return to the plant. Reinstallation involves the routine closure of gasketed joints which is verified subsequently through inservice leakage 1esting.

Based on the above, a valid OM Part 1 performance test of the Pressurizer and Ma4'1 Steam Satety Valves can be had through either in-place testing or testing in a lab.

SUBSTIl0TE TEST For the purpase nf accomplishing Main Steam and Pressurizer Lafesy Valve testing prior to initial elect ric power generation, the f ollowing requirements will apoly:

1. Within 6 months of initial fuel loading, each Pressurizer Safety Valve shall have its set pressure verified, E. Either before or after installation and within 6 months prior to initial reactor criticality, each Main 5 team Safety Valve shall be subjected to the following tests:

a) set pressure verification b) compliance with the Owner's seat tightness crite.'ia shall be verified.

APPROVAL STATUS (lateri

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