ML19263E264

Respond to IE Bulletin 79-04,Incorrect Weights for Swing Check Valves Mfg by Velan Engineering Corp. Lists Installed Valves by Sys,Number of Valves & Valve Size

ML19263E264
Person / Time
Site:	Pilgrim
Issue date:	05/01/1979
From:	Andognini G BOSTON EDISON CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
79-84, NUDOCS 7906050435
Download: ML19263E264 (3)

Text

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Id k BOSTON EDIDON COMPANY GENERAL OFFICES 000 SQYLaTON STREET GOSTON. M A S S AC H u s ETTs D 219 9 G. CARL ANDOGNIN1 MANAGCR NUCLEAR OPERATIONS DEPARTMENT

-,'~.. May 1, 1979

N-..._ BECo. Ltr. #79-84

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Mr. Boyce H. Grier ' ' ~~ w Office of Inspection and Enforcement Region I U.S. Nuclear Regulatory Commission "'s_ ,'

631 Park Avenue s. _ '

King of Prussia, PA. 19406 ' '-

Licence No. DPR-35 Docket No. 50-293 Response to IE Bulletin #79-04

Dear Sir:

In a letter dated March 30, 1979, you transmitted IE Bulletin #79-04 titled,

" Incorrect Weights For Swing Check Valves Manufactured By Velan Engineering Corporation". Boston Edison Company was requested to take the following actions to review this problem at Pilgrim Nuclear Power Station:

1. List all Seismic Category I piping systems (or portions thereof) where 3, 4, or 6 inch diam 2ter Velan swing check valves are installed or are scheduled to be installed.

Response

An examination of Seismic Category I piping systems showed the subject 3, 4, or 6 inch Velan swing check valves to be installed in the below listed systems.

Systen Numbers of Valves Size HPCI Min. Recire. Line 1 4" Core Spray Pump Test 2 6" RHR Makeup Cond. Trans. 1 6" Fuel Pool Cooling 1 3" 2300 184 7906050 6 [

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DDSTON EoiscN COMPANY Mr. Boyce H. Grier May 1, 1979 Page 2

2. Verify for all those systems identified in item 1 above that correct check valve weights were used in the piping analysis. Explain how and when the correct valve weights were determined.

Response

The Velan Valve Company was contacted to determine if ths valve weights shown on project drawings were correct. Velan subsequently verified by weighing types of valves on an as built basis, and found the weights on the Pilgrim Project drawings to be correct. Boston Edison Company was informed of this on April 23, 1979.

We then examined the piping analysis to verify that correct weights were used in the calculations and some slight discrepencies were found. An examination of the stress analysis report for lines containing these

- m m valves showed that "as calculated" values were more conservative than

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~~1.f the corrected weights were used for 3 of the systems listed.

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3. If inco[re'cE" valva. weights were used, explain what actions have been taken or are planned'~tusre-evaluate the piping systems affected.

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Our plan of action is to re-analyze the af fected piping syas' ems substi-tuting the correct valve weights in our calculations. This prutir.inary re-analysis to date shows that the seismic stresses and loads are belo'V's ,,

the maximum allowable limits and no significant changes are anticipated ' ' ~ ,

in the outcome of the final analysis. Should the final analysis indicate any discrepencies you will be immediately notified of a new plan of action.

4. Specify for all the affected systems identified in Item I whether modifica-tions were or are required er the piping systems or their supports because of changes in valve weight. Also, include the basis for this determination.

For those systems in which the actual valve weight is greater than the de-sign weight provide a summary of stresses and loads and their allowable limits for the piping and its supports.

Response

Of the systems identified in Item 1, one case was found to have an actual valve weight greater than the design weight. However utilizing the criterion outlined in our FSAR Appendix A " Pressure Integrity of Piping and Equipment Pressure Parts", the preliminary calculations indicate that the allowable limits for stresses and loads for the piping and its supports do not exceed the original design criteria and therefore no modifications are considered necessary. A summary of stresses and loads for the affected system will be forwarded to you upon its completion but no later than June 1, 1979.

2300 185

BOSTON EDISON COMPANY Mr. Boyce H. Grier May 1, 1979 Page 3

5. Identify the analytical technique including identification of any computer codes used to determine the stresses indicated in Item 4.

Response

The analytical technique utilized to determine the seismic stresses in Item 4 is the Bechtel Topical Report BP-TOP-1, Rev. 3, January, 1976, titled " Seismic Analysis of Piping Systems".

Original piping calculations were made using the following computer codes:

Code Written By Verified By

1. ME-632 Bechtel Power Corp. PISOL (EDS Nuclear),

PIPESD (UC Berkley &

John A. Blume & Assoc.)

TPIPE (PMP Systens Engineering Inc.)

2. PISOL EDS Nuclear NUPIPE (Nuclear Ser-vices Corp.) PIPESD, ADLPIPE (Arthur D.

Little Corp) ME 101 (Bechtel Power Corp.)

If there are any further questions on this subject please feel free to contact us at your convenience.

- ~ , Very truly yours,

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c[: Director - . .

Office of Inspection and Enforcement .

Division of Reactor Operations Inspection -

Washington, D. C. 20555 2300 186