ML20091A614
| ML20091A614 | |
| Person / Time | |
|---|---|
| Site: | Midland |
| Issue date: | 05/19/1984 |
| From: | Jackie Cook CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| 30284, 84-07-#1, 84-7-#1, OL, OM, NUDOCS 8405300032 | |
| Download: ML20091A614 (8) | |
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Consumers Power James W Cook h fhf Vice President - Projects, Engineering and Construction General officos: 1945 West Parnell Road, Jackson, MI 4926 + (517) 788-0453 May 19, 1984 84-07 #1 Mr J G Keppler, Rcgional Administrator US Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 60137 MIDLAND ENERGY CENTER PROJECT DOCKET NOS 50-329 AND 50-330 P7.PE WHIP RESTRAINTS - NSSS COLD LEG PIPING FILE:
0.4.9.94 SERIAL: 30284 On April 19, 1984, Consumers Power Company notified your staff of a potential 10CFR50.55(e) condition involving the design of pipe whip restraints for NSSS cold leg piping. This letter is a final report.
Because of the extensive evaluation required to determine whether the safety of plant operations would have been adversely affected, this condition is considered reportable under 10CFR50.55(e).
Attachments 1 and 2 provide descriptions cf the investigation that took place, the probable causes and the planned corrective action.
JWC/AHB/lr Attachments 1: MCAR-84, Initial Is ue, dated April 24, 1984 2: MCAR 84 Final Report, dated May 16, 1984 CC: Document Control Desk, NRC Washington, DC BBurgess, NRC Resident Inspector Midland Nuclear Plant DHood, USNRC Office-of NRR INP0 Records Center 8405300032 840519 ggg PDR ADOCK 05000329 PDR n-S x 6g' l OC0584-0036A-MP01
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2 Serial 30294 84-07 #1 OM/0L SERVICE LIST Mr Frank J.Kelley Atomic" Safety & Licensing Attorney General of the Appeal Board Ms Carole Steinberg ~
U S Nuclear Regulatory Commission
-State of Michigan Washington, DC 20555
' Assistant Attorney General Environmental Protection Division Mr C R Stephene (3) 720 Law Building Chief, Docketing & Services
-Lansing, MI 48913 U S Nuclear Regulatory Commission Office of the Secretary Washington, DC 20555 Mr Myron M Cherry, Esq Suite 3700 Ms Mary Sinclair Three First National Plaza 5711 Summerset Street Chicago, IL 60602 Midland, MI 48640
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Mr Wendell H Marshall Mr William D Paton, Esq RFD 10 Counsel for the NRC Staff Midland, MI 48640 U S Nuclear Regulatcry Commission Washington, DC 20555 Mr Charles Bechhoefer, Esq Atomic Safety & Licensing Atomic Safety & Licensing Board Panel Board Panel U S Nucien.r Regulatory Camuitsion U S Nuclear Regulatory Commission East-West Towers, Poem E-413 Washington, DC 20555 Bethesda, MD 20014-Ms Barbara Stamaris Dr Frederick P Cowan 5795 ?lorth River Road 6152 8 Verde Trail-Rt 3 Art 3-125 Freeland, M1 48623 Boca Raton, FL 33433 Dr Jerry Harbour Mr Fred C Williams Atomic Safety & Licensing Isham, Lincoln & Beale Board Panel 1120 Connecticut Ave, NW, Suite 840 U S Nuclear Regulatory Commission Washington, DC 20036 East-West Towers, Room E-454 Bethesda, MD 20014 Mr James E Brunner, Esq Consumers Power Company Mr M I Miller, Esq 212 West Michigan Avenue Isham, Lincoln & Beale Jackson, MI 49201 Three First National Plaza 52nd Floor Chicago, IL 60602
=0C0584-0036A-MP01
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3 Serial 30294 84-07 #1
' Mr D'F Judd Babcock & Wilcox PO Box.1260-Mr John Demeester, Esq
' Lynchburg, VA 24505 Dow Chemical Building Michigan. Division
~ Mr Steve Gadler, Esq Midland MI 48640
. 2120 Carter Avenue l
St Paul, MN 55108 Ms Lynne Bernabei Government Accountability Project
- Mr P Robert Brown 1901 Q Street, b51 Clark, Klein & Beaumont Washington, DC 20009
- 1600 First Federal Bldg Woodward Ave Detroit, MI 48226.
3/14/84 F
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- OC0584-0036A-MP01-
l fk88ll Serial 30284 l
gm QUALITY ASSURANCF. PROGRAM Q).
MANAGEMENT CORRECTIVE ACTION REPORT MCAR 1 REPORT NO. 84
_g JOB NO.
7220 Q NO.
DATE 4/23/84 l* DESCRIPTION (including references):
This report addresses a concern with the pipe whip restraint design on the NSSS lower cold leg piping, which was documented by Consumers Power Company in Safety Concern and Reportability Evaluati'on (SCRE) 81.
Continued on page 2
- RECOMMENDED ACTION (Optional) 1.
Provide appropriate design modifications to correct above conditions.
2.
Investigate for related conditions and for similar conditions by other project groups.
3.
Determine root cause and provide corrective action to preclude recurrence.
4.
Issue first report by 5/11/84.
REFERRED TO OD ENGINEERING O CONSTRUCTION O OA MANAGEMENT O
O PROCUREMENT ISSUED BY M NbI
- This condition was reported to the NRC by CPCo fo r Project OA EnginMr
~Date
_ a s notentially reportable on 4/19/84.
11 REPORTABLE DEFICIENCY NOTIFIED CLIENT M
E YES @**
O NO
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V~
E ete D
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!!! CAUSE CO75RECTIVE ACTION TAKEN AUTHORIZED BY STANDARD DISTRIBUTON ADDfTONAL DISTRIBUTON AS APPROPRIATE DMSON OA MANAGER ENGINEERING MANAGER FORMAL REPORTTO CLIENT MANAGER OF OA BPC PROJECT ENGINEER (If Section11 Applies)
Date GPD - OA MANAGER OE SUPERVISOR LAPD OA MANAGER SFPD OA MANAGER CONSTRUCTON MANAGER PROJECT MANAGER PROJ SUPT /PROJ CONSTR MANAGER CUENT CHIEF CONSTR OC ENGINEER CORRECTIVE ACTION lMPLEMENTED DMSON PROCURENT MGR PROJ PROCUREMENT MGR PROCUREMENT SUPPUER OUAUTY MGR AND OfV SUPPUER QUAUTY MGR VERIFIED BY Project OA Engineer Date j
'Descree in space provided and attach reference document.
AAPD-0181
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,MCAR 84 Page 2 l488II DESCRIPTION (continued):
Pipe Whip Restraints 4 and 7 (typicals) on the NSSS lower cold leg piping were designed by Bechtel to be supported by the lower cold legs. There are a total of 8 subject restraints per unit, 2 on each steam generator cold leg. The Babcock & Wilcox (B&W) analysis of the NS,SS did not account for the effects of the deadweight of these restraints on the NSSS during normal operation, safe shutdown earthquake (SSE), or loss-of-coolant accident (LOCA). This could have resulted in underestimated loadings on B&W components and Bechtel NSSS supports, and new system responses at the attachment points of Bechtel piping to the NSSS. In addition, B&W stated that the restraints could have induced potentially adverse vibrations on the NSSS during normal operation due to the eccentrically hung restraint mass.
Bechtel is currently redesigning these restraints to be completely supported by the basemat with no contact on the lower cold leg piping during normal operation. As a result, no reanalysis of the NSSS will be performed by B&W and no study will be conducted by B&W on the NSSS for potential vibration-induced problems.
Therefore, the evaluation of whether the subject restraints, if left attached to the NSSS piping, could have adversely affected the safety of operations of the Midland plant is indeterminate because no definitive statements can be made without the above reanalysis and study.
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Serial 30284
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Becggociates Professional Corporation
SUBJECT:
MCAR 84 Pipe Whip Restraints on NSSS Lower Cold Leg Piping FINAL REPORT DATE:
May 16, 1984 PROJECT: Consumers Power Company Midland Plant Units 1 and 2 Bechtel Job 7220 Introduction This report addresses a concern with the pipe whip restraint design on the NSSS lower cold leg piping, which was documented by Consumers Power Company in Safety Concern and Reportability Evaluation (SCRE) 81.
Description of Concern Pipe Whip Restraints 4 and 7 on the NSSS lower cold leg piping were designed by Bechtel to be supported by the lower cold legs (Reference A).
The B&W analysis of the NSSS did not account for the effects of the deadweight of these restraints on the NSSS during normal cperation, safe shutdown earthquake (SSE), or loss-of-coolant accident (LOCA). This could have resulted in underesticated loading on B&W components and Bechtel NSSS supports, and new system responses at the attachment points of Eechtel piping to the NSSS.
In cdditiva, B5V stated that the restraints could have induced potentially adverse vibretions on the NSSS during normal operation due to the eccentrically hung restraint mass.
_ Historical Background Restraints 4 and 7 are located at the elbow of the lower cold leg piping near the outlet of the steam generators. These restraints were originally designed by Bechtel to limit the displacement of the piping after a LOCA at the steam generator outlet nozzle in order to prevent overpressurization of the steam generator skirt. The Bechtel design (Reference A) included straps around the cold leg piping to support the i
restraints. Bechtel was advised that the restraint design was not acceptable to B&W in January 1983 (Reference D).
j Summary of Investigation Consumers Power Company issued SCRE 81 concerning this subject on April 4, 1983. Bechtel conducted its investigation and prepared a corresponding safety evaluation (Reference B) on September 2, 1983. No other Bechtel pipe whip restraints were found to be supported by vendor piping.
For Bechtel pipe whip restraints supported by Bechtel piping, the additional deadweight is accommodated by the design of the piping and pipe supports.
Bechtel Associates Professional Corporation
\\5ll04 l5fl64 MCAR 84 FINAL REPORT Page 2 Analysis of Safety Implication The evaluation of whether the subject restraints, if left attached to the NSSS piping, could have adversely affected the safety of operations of the Midland plant is indeterminate without further analysis. The current redesign of the subject restraints conforms to the configuration analytically assumed by B&W.
Further analysis is therefore unnecessary and will not be performed.
Probable Cause The exclusion of the deadweight of the subject restraints from the B&W NSSS analysis is attributable to two factors:
1.
A misinterpretation of the Bechtel design drawing by B&W.
2.
The deadweight of the restraints was not included in the initial issue of the Bechtel Input Document (BID).
Corrective Action A.
Reference C documents Consumers Power Company direction for Bechtel to redesign Restraints 4 and 7 to be completely supported by the basemat and to not contact the lower cold leg piping during normal operation.
Bechtel is currently redesigning these restraints in accordance with that direction. The actions and senedule for issuing this redesign are as follows:
Responsibility Action Date Bechtel 1.
Reissue Bechtel Sketch 7220-SKC-880, 8/15/84F (Civil)
Rev A, (which shows the redesign) as Bechtel Drawing 7220-C-477-2(Q),
Rev 0.
Bechtel 2.
Revise the BID to include Bechtel 8/29/84F (Nuclear)
Drawing 7220-C-477-2(Q), Rev 0 and to delete the deadweight values for the subject restraints.
l B.
This concern is judged by Bechtel to be an isolates incident. No additional corrective action to preclude recurrence is necessary because 1) adequate controls are currently in place through the BID
Bechtel Associates Professional Corporation 15l104 I5II64 MCAR 84 FINAL REPORT Page 3 and its procedure (PEP 4.25.6), and 2) communica: ions channels between Bechtel and B&W for pipe whip restraints have br.en expanded to promote a mutual understanding of the restraint design and its effect on the B&W analysis. Even though this concern was not recognized in a time frame consistent with the completion of the B&W analysis, the concern was discovered during the B&W review of the governing Bechtel drawing contained in the BID.
Reportability This concern was verbally communicated te the NRC by Consumers Power Company on April 19, 1984.
It was class.'.fied as potentially reportable under the criteria contained in 10 CFR 5J.55(e).
References A)
Bechtel Drawing 7220-C-477(Q)
B)
Bechtel letter MAD-2537, 9/2/83 C)
CPCo Letter Serla' 22664, 5/5/83 (com 114680)
D)
Meeting Notes No.13C3, EL(,-16100, 3/2/83 (Con.106903)
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Submitted by:
a M E.4. Poser V ggg Project Engineering Manager Approved b :
VN
..E.M. Hughes Chief Nuclear Engineer
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i Approve y: /
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g E.H. Smi'f h g
Engineering Manager I
Concurrence by:
fyMA.Dietrich Project Quality Assurance Engineer 050105/4
.