ML19332A006

Final Deficiency Rept Re Incorrect Bolt Torquing on HPCS Pump.Deficiency Could Have Caused Pump Degradation & Subsequent Failure.Pumps Disassembled & Retorqued to Field Disposition Instruction 32-42382

ML19332A006
Person / Time
Site:	Grand Gulf
Issue date:	08/04/1980
From:	Mcgaughy J MISSISSIPPI POWER & LIGHT CO.
To:
References
10CFR-050.55E, 10CFR-50.55E, AECM-80-182, NUDOCS 8009100303
Download: ML19332A006 (4)

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' MISSISSIPPI POWER s EfGHT' COhllPANY Helping Build Mississippi MISSISSIPPI 39205 P. O. B O X 16 4 0. J A C K S Q, ,MG 12 Alf :

NUCLEAR PRooUCTioN DEPARTMENT l2 Auguse 4, 1980 Office of Inspection & EMorcement U. S. Nuclear Regulatory Commission Region II '

101 Marietta Street, N.W.

Suite 3100 Atlanta, Georgia 30303 Attention: Mr. J. P. O'Reilly, Director

SUBJECT:

Grand Gulf Nuclear Station Units 1 and 2 Docket Nos. 50-416/417 File 0260/15525/15526 PRD-80/17, Final Report, Incorrect ,

Bolt Torquing on High Pressure I Core Spray Pump AECM-80/182

Reference:

AECM-80/99, 5/9/80 On April 10, 1980, Mississippi Power & Light Company notified Mr. F. Cantrell of your office of a Potentially Reportable Defi-ciency (PRD) at the Grand Gulf Nuclear Station (GGNS) construction site. The deficiency concerns out of specification bolt torque values noted on the High Pressure Core Spray (HPCS) pump. The pump was manufactured by the Byron Jackson Pump Division of Borg Warner Corporation and was procured by General Electric for use at GGNS. l We have determined this deficiency to be reportable within the

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meaning of both 10CFR50.55(e) and 10CFR21. Our final reports are attached.

Yours truly, gy J. P. McGaughy, Jr.

Assistant Vice President, Nuclear Production ATR:mt Attachment gii r S ')

UritCLE C0pr 8 00910 0 b 3 Member Mwdle South utmeies System 3

MISSISSIPPI POWER & LIGHT COMPANY Mr. J.' P. O'Reilly- AECM-80/182 NRC Page 2 J

} cc: Mr. N. L. Stampley i Mr. R.'B. McGehee Mr. T. B. Conner Mr. Victor Stello,' Director , w/3 Division of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555 i

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p Attachment to AECM-80/182

" Page 1 of 1 FINAL REPORT FOR PRD-80/17 I. Description of Deficiency The NSSS Supplier issued a Field Disposition Instruction (FDI

1. 32-42382) on August 7, 1978. The purpose of the FDI was to update the ECCS Pump Technical Manuals pending their revision. Speci-fically, the FDI updated the bolt torquing procedure to vendor preferred values. The pumps in questien were chose provided for the Residual Heat Removal (RHR), Low Pressure Core Spray (LPCS) and High Pressure Core Spray (HPCS) Systems. Based on the FDI, the tenth (10th) stage of the HPCS pump was disassembled and the thrust collar bolts ( " dia. x 13 UNC) were checked for actual torque values. This check revealed that the actual terque values varied frem 25-43 ft. Ibs. These va;ues were centrary to the vendor specified original torquing rvquirement of 15 ft.

lbs. as well as the updated torquing values of 40-55 f t. lbs.

specified by the FDI. Based on this preliminary check, the sample size was increased to check the actual torque values for the case bolts and thrust collar cap screws of the sixth (6th), seventh (7th),

eighth (8th), and ninth (9th) stage of the HPCS pump. This check revealed additional inconsistencies in torquing values; for ex-ample, a number of 1 3/6" dia. casing studs were found 225 ft.

lbs. lower than the minimum NSSS Supplier values.

II. Safety Implications i

Had this condition remained uncorrected, the inconsistency in the '

"as asse= bled" torque values found within a stage of the pump could lead to unbalanced load distribution causing undue wear and vibration. This could result in pump degradation and a sub-sequent f ailure of the pump to perform its intended safety functien.

III. Corrective Action The ECCS Pumps for Unit I have been disassembled and retorqued to the values specified by the FDI. The Unit II ECCS pumps will be disassembled and retorqued to the appropriate values during system inspection and chechout. Details of this condition are available at the plant site in Bechtel MCAR GCNS 71 and MP&L PRD-80/17.

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10 CTR PART 21 RFPORT

1. Identification of individual (s) Informina the NRC:

Naee(s): W. D. Hays A. T. Ramey Telephone call to M. Hunt, NRC, Region II, 8/5/80.

.Addregn: Miss*ssippi Power & Light Company. P. O. Bnx 1% 0. Jackson MS 39203

2. Identification of entity failing to comply or containing a defect (check appropriate blecka):

CRAND C'JLF NUCLtAR STATION Unit 1C Lait 2 C Other (Specify)

3. sm iter:

General Electric Co.

Nuclear Engineering Division San Jose, CA 1

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4. Nature of the defect of f ailure to comply and the safety hazard which is creatcJ or could be created by such defect or failure to comply:

See paragraphs I & II to Attach: ent A to AEC'! c0/182.

5. Date information obtained for this report: 8/4/80 l

o. Additicnal information for defective cemenents incerporated in other facilities, at applicable:

1 Number in use, surrlied for, Facilitv/Locatien l or beine carrlied (This informatien is not available to MP&L)

7. Corrective Action: See paragraph III to Attachment A to AECM-80/182.

Re sponsibilit y : Mississirpt Pewer & Liche Qua!!tv Assurance Secett (Name cf individual or organization)

Time Required To Comolete Action: Began: 4/14/80, Comolete for Unit 1: L' nit 2 corrective action ecmplete by Unit 2 Fuel load, clo m of MCAR-71.

8. Advice related to the defect or failure to comply about the facility, activity, or basic corronent that has been, is being, or will be given to purchasers or licensees:

None given at this time (NOTE: General Electric Comoany stated that !5ev do not agree that this cendition shculd be reported under either 10CFR50.55(e) or 10CFE21.)