ML20155C276

Final Deficiency Rept Re Use of Nonconservative Analyses of Insulation Weights for Valves & Pipe Fittings.Initially Reported on 840123.Corrective Actions Will Be Completed 6 Months Prior to Fuel Load

ML20155C276
Person / Time
Site:	Bellefonte
Issue date:	04/04/1986
From:	Gridley R TENNESSEE VALLEY AUTHORITY
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NUDOCS 8604170001
Download: ML20155C276 (2)

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TENNESSEE VALLEY AUTHORITY SN 157B Lookout Place o d [M 0 Aphi 4, 986 BLRD-50-438/84-09 BLRD-50-439/84-08 U.S. Nuclear Regulatory Commission Region II Attn: Dr. J. Nelson Grace, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323

Dear Dr. Grace:

BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - INSULATION WEIGHTS ASSUMED IN l ANALYSES FOR VALVES AND PIPE FITTINGS - BLRD-50-438/84-09, BLRD-50-439/84 FINAL REPORT The subject deficiency was initially reported to NRC-OIE Inspector P. E. Fredrickson on January 23, 1984 in accordance with 10 CFR 50.55(e) as

-NCR BLN CEB 8401. Our interim reports were submitted on February 16 and April 15, 1985. Enclosed is our final report.

If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.

Very truly yours, TENNESSEE VALLEY AUTHORITY e d. -

R.L.Gridle[

Manager of Licensing Enclosure ec: Mr. James Taylor, Director (Enclosure)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Conunission Washington, D.C. 20555 Records Center (Enclosure)

Institute of Nuclear Power Operations

~1100 circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 8604170001 860404 PDR ADOCK 05000438 8 PDR I

An Equal Opportunity Employer i f

5 ENCLOSURE BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 INSULATION WEIGHTS ASSUMED IN ANALYSES FOR VALVES AND PIPE FITTINGS

] BLRD-50-438/84-09 AND BLRD-50-439/84-08 NCR BLN CEB 8401 10 CFR 50.55(e)

FINAL REPOR

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1 Description of Deficiency TVA's Civil Engineering Branch (CEB) Engineering Procedure (EP) 21.12, revision 2 Table 5.4-5, and Bellefonte Engineering Project (BLEP) drawing i 3BT0001-00-01 list. valve and pipe fitting adjustment factors for insulation weight calculations. These adjustment factors take the fitting or valve

length and diameter into consideration. The factor is multiplied by the weight per foot of pipe insulation to yield an insulation weight value per valve or fitting. The analysts used these factors and assumed the results were a weight per foot value which was to be converted to a weight value in the analyses -- creating some unconservative results. The deficiency does not 1 constitute a generic condition for other Bellefonte work or that of other TVA (

plants.

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The cause of this deficiency is that analysts were not aware of the units for the calculated results (the dimension-units of the weight adjustment factors were not supplied in the Bellefonte Analysic Handbook). Therefore, the -

, analysts erroneously assumed that the calculated result units were pounds per foot.

Safety Implications l The use of nonconservative analyses in the design of seismic piping supports

- could result in inadequate support designs and installations. Therefore, if this condition had remained uncorrected, the' safe operation of the plant could have been adversely affected.

Corrective Action i '

All analysis problems have been reviewed and those deficient in units of weight for insulation have been identified. Action is currently underway to track and correct the deficient problems involved. All affected piping systems will be reanalyzed. Piping supports will be redesigned and reworked as required. All action to correct the deficient condition for units 1 and 2 will be complete six months before fuel. loading of the respective unit.

The Bellefonte rigorous piping analysis verification checklist, BLN-RAH-401, was issued on March 5, 1984, and included the requirement to check the application of the insulation weight adjustment factor (s). Additional instructions will be provided in a policy statement to the BLN Rigorous Analysis Handbook by April 1, 1986, to ensure that the analyst is aware of the

,'- results that must be obtained by applying the adjustment factor (s). This will complete the action required to prevent recurrence.

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