ML20137Y876
| ML20137Y876 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 02/27/1986 |
| From: | Gridley R TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8603120410 | |
| Download: ML20137Y876 (3) | |
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l TENNESSEE VALLEY AUTHORITY CH ATTANOOGA. TENNESSEE 37401 SN 151B Lookout Place 1
February 27, 1986 c
u, BLHD-50-438,83-14 3
bLHD-50-439/83-10 C
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U.S. Nuclear Regulatory Commission Reglon II "O
Attention:
Dr. J. Nelson Crace, Regional Administrator
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i 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323
Dear Dr. Grace:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - MAKEUP AND PURIFICATION LETDOWN COOLER INLET / OUTLET PIPING REVERSED - BLRD-50-438/83 -14, BLHD-50-439/83 '
F_INAL REPO_RT i
The subject deficiency was initially reported to NHC-0IE luspector D. M. Vercelli on January 24, 1983 in accordancu with 10 CFR 50.55(e) as NCR t
BLN BLP 8303. This was followed by our interim reports dated February 18 and December 7, 1983.
Enclosed is our final report.
[
f If there are any questions, please get in touch with H. H. Shell at FTS 858-2688.
I I
Very truly yours, TENNESSEE LLEY AUTHORITY
/
1 R.
. Gridle Manager of.lcensing Enclosure cc:
Mr. James Taylor, Director (Enclosure)
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Office of Inspection and Enforcement U.S. Nuclear Regulatory CommLssion t
Washington, D.C.
20555 i
Records Center (Enclosure)
Institute of Nuclear Power Operations 1100 circle 15 Parkway, Suite 1500 l
Allanta, coorgia 30339 4
1 9603120410 227 ADOCM 0 38 gDR DR An Equal Opportunity Employer l
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s ENCLOGURE BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 MAKEUP AND PURIFICATION LETDOWN COOLER INLET /0UTLET PIPING REVERSED DLRD 50-438/83-14, 50 439/83-10 NCR BLN BLp 8303 10 CFR 50.55(e)
FINAL _ItEpOR_T D,escription of Deficiency The makeup and purification letdown coolers INV-HCLR-008 and 2NV-HCLR-001 are mounted such that snakeup/ purification letdown line inlet piping la connected to the cooler outlet nozzle, and the outlet piping is connected to the cooler inlet nozzle. The letdown cooler inlet nozzio is provided with an Inconel tubo sheet to accomodato the high letdown water temperature.
Under the above arrangement, the outlet nozzio of the indicated coolers would be subjected to a condition for which it was not designed.
The condition existed because the design of the piping and tho mounting of the coolors were based on opposite hand coolors; in reality, the coolers are identical. The condition went unnoticed until the problem was discovered during a sito inspection by Babcock and Wilcox personnel who were reviewing an unrelated problem with the letdown coolers.
Because the coolers uit un opposite walls of the cooler roam and because the inlet and outlet piping are routed opposite hand, cooler support designers and piping designers assumed the coolers were opposite hand and made their designs accordingly. They failed to adequately review the vendors drawings to confirm their ausumption.
This is an isolated occurrence and is not applicable to other TVA nuclear plants.
Sa f etty_ Imp _1,1c_a t i.ons, The makeup / purification letdown piping to the letdown coolers is part of the reactor coolant system pressure boundary. The cited piping arrangement would have cubjected the cooler oullot nozzle to a temperature for which it was not dec1gned, pocalbly causing a piping rupture with a reuultant LOCA condLLlon.
Consequently, had this condillon remained uncorrected, the safe operation of the plant could have been adversely affected.
Correctivo Action Lotdown coolers INV-HCLR-000 and 2NV-HCLR 001 were Iriverted to establish the correct inict/ outlet relationuhip be* ween the letdown linou and the letdown coolers. The design work completerd under engineering chango notico (hCN) 1#> /8 as a renult of this action tu as (nllown;
i o
i a 1.
Component cooling water piping was rerouted.
2.
A unit 2 makeup and purificallon vent line was rerouted.
3.
Letdown cooler supports were redesigned.
4.
Unit 1 supports for the component cooling water and makeup and purification systems were redesigned.
Unit 2 supports for the component cooling water and makeup and purification systems are being redesigned under ECt! 2885 and will be completed no later than one year before unit 2 fuel load.
Designora and engineers have been trained--per ORP-10, which requires interface reviews between disciplines and the review of vendor documents.
This will provent future deficiencies of this nature.
All construction activitiec involving cooler 1NV-HCLR-008 (unit 1) will be completed six months beforo unit i fuel load, and all construction activitics involving cooler 2tiV-MCLR-001 (unit 2) will be completed no latur than six months before unit 2 fuel load.
I e
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