ML20028G158

Fifth Interim Deficiency Rept Re Sheared Bolts on Diesel Generator Rear Crankcase Cover.Initially Reported on 820322. Final Rept Will Be Submitted by 830601.Also Reportable Per 10CFR21 for Unit 1

ML20028G158
Person / Time
Site:	Grand Gulf
Issue date:	01/31/1983
From:	Mcgaughy J MISSISSIPPI POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
REF-PT21-83 10CFR-050.55E, 10CFR-50.55E, AECM-83-0070, AECM-83-70, NUDOCS 8302070466
Download: ML20028G158 (2)

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MISSISSIPPI POWER & LIGHT COMPANY

] Helping Build Mississippi EiElmMddu P. O. B OX 164 0. J AC K S O N. MIS SIS SIP PI 3 9 205 JAMES P. MMMUGHY. JR January 31, 1983 AS$187 ANT VICE PRESIDENT Of fice of Inspection & Enforcement U. S. Nuclear Regulatory Commission Region II -

101 Marietta Street, N.W. '"

Suite 3100 ~]

l Atlanta, Georgia 30303 a l ro Attention: Mr. J. P. O'Reilly, Regional Administrator C

Dear Mr. O'Reilly.

SUBJECT:

Grand Gulf NucledW' Station Units 1 and 2 J' License No. NPF-13 Docket Nos. 50-416/417 -

File 0260/15525/15526 PRD-82/14, Interim Report No. 5, Sheared Bolts on Diesel Generator Rear Crankcase Cover AECM-83/0070

References:

AECM-82/176, 4/21/82 AECM-82/288, 6/2 5/82 AhCH-82/380, 9/7/82 AECM-82 / 521, 11/8/ 82 On March 22, 1982, Mississippi Power & Light Company notified Mr. R.

Butcher, of your of fice, of a Potentially Repartable Deficiency (PRD) at the Grand Gul f Nuclear Station (CGNS) conatruction site. The deficiency concerns sheared bolts on the rear crankcase cover of the Delaval diesel generators.

As previously reported, MP&L has evaluated this deficiency and determined that it is reportable under the provisions of 10CFR50.55(e) and 10CFR21 for Unit 1, and 10CFR50.55(e) for Unit 2.

The only additional inforetation MP&L has at this time is that:

1. DCP-82 /4183 has been initiated and released for construction to replace the rear crankcase cover bolts with more fatigue resistant bolts. The new bolts would be installed as per Delaval's suggested disposition to use Loctite-271 and increase the torque to 100 ft. Ibs. Tab washers would also be used.

2. A proposed program is being developed to instrument the diesel and collect data during a test run. Delaval indicated that the cause of the bolt failures was vibration of the cover plate induced by the firing of the rear cylindtr.

8302070466 830131 e PDR ADOCK t 5 300416 S

tC OYUcW . C*

PDR Member Middle South Utilities System gO.-

Mr.-J. P. O'Reilly AECM-83/0070 NRC Page 2 A Final Report will be submitted when the data in 2. above has been collected, analyzed and determinations are made as to a. the cause of the fatigue f ailures of the bolts and b. possible further corrective actions. MP&L expects this to be completed by June.1, 1983.

Yours tru y,

?

l vJ. P. McGaug y Jr.

ACP;dr cc: Mr. N. L. Stampley Mr. R. B. McGehee

.Mr. T. B. Conner Mr. Richard C. DeYoung, Director Of fice of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555

'Mr. G. B. Taylor South Miss. Electric Power Association P. O. Box 1589 Hattiesburg, MS 39401 p

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