U-602579, Part 21 Rept Re Ideal Generators Installed W/Edgs Having Greater Generator Rotor Mass than Originally Calculated. Evaluated Impact of Issue of Generator Frequency & Torsional Vibration Prior to Interim Rept

Part 21 Rept Re Ideal Generators Installed W/Edgs Having Greater Generator Rotor Mass than Originally Calculated. Evaluated Impact of Issue of Generator Frequency & Torsional Vibration Prior to Interim Rept

ML20108D166
Person / Time
Site:	Clinton
Issue date:	05/02/1996
From:	Connell W ILLINOIS POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
REF-PT21-96 U-602579, WC-145-96, NUDOCS 9605070306
Download: ML20108D166 (2)

Text

lilinois Power Company

/*

• Clinton Power Station

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• P.o. Box 678

, Clinton. IL 61727 Tel 217 935-5623 Fax 217 935-4632 Wilfred Connell Vice President ILLIN915 U-(>02579 P4MR 4r.14o WC-145-96 May 2, 1996 Docket No. 50-461 10CFR21.21 Document Control Desk Nuclear Regulatory Commission Washington, D.C. 20555 .

i Sub' ject: 10CFR21 Final Report 21-96-001: Ideal Generators -

Installed with Emergency Diesel Generators Have .

Generator Rotor Mass Greater Than Originally Calculated

Dear Sir:

i On January 15,1996, Illinois Power (IP) identified a condition involving the  ;

Divisions 1 and 2 Emergency Diesel Generators (EI.'Gs) as potentially reportable under )

the provisions of10CFR21. Specifically, Condition Report (CR) 1-96-01-029 was '

initiated to identify that Ideal Electric, the manufacturer of the generator portion of the EDGs, had discovered that the mass of the generator rotors had been incorrectly calculated. The revised calculation shows a larger rotor mass and rotational inertia. IP 3

purchased the EDG units from Stewart & Stevenson. The generators are Ideal model l

numbers SA6-50 and SA6-44, and Ideal drawings B-MED-221 and B-MED-217. )

On March 13,1996, IP submitted an interim report (IP letter U-602564) to inform the NRC that the reportability evaluation for the condition was not complete. In that report, IP noted that an evaluation of the impact of the condition on the seismic qualification of the diesel generator units was complete and concluded that the larger rotor mass has no adverse impact on the units. The interim report further noted that IP had not completed an evaluation of the impact of the larger rotor mass on the frequency and torsional analysis of the units. Prior to the interim report, a preliminary review of the impact of this issue on generator frequency and torsional vibration had been performed l

and additional evaluation was to follow. The preliminary review had found the condition acceptable.

IP has completed an evaluation of the impact of this condition on the frequency and torsional analysis of the units and concludes that the larger rotor mass does not have an adverse impact on the ability of the Divisions 1 and 2 EDGs to perform their intended design function. Therefore, on the basis that this condition could not create a substantial safety hazard, it is not reportable under the provisions of 10CFR21.

S 07001o 9605070306 960502 PDR ADOCK 05000461 PDR _

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• U-602579 Page 2 l .

Additional information regarding this issue may be obtained by contacting S. P.

l Hong, Plant Engineering, at (217) 935-8881, extension 3464.

Sincerely yours, fg ( 0nd'#

Wilf Vice President l RSF/csm cc: NRC Clinton Licensing Project Manager NRC Resident Office, V-690 Regional Administrator, Region III, USNRC l Illinois Department of Nuclear Safety

! INPO Records Center Ideal Electric Stewart & Stevenson l

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