ML20235U029

Part 21 Rept Re Velan Maint Manual VEL-FBBM 2 1/2-24 Inch Forged Bolted Bonnet Gate & Globe Valves & Bolted Cover Check Valves.Investigation Revealed That Dry Film Lubricant Not Appropriate.Lubrication Manual Revised

ML20235U029
Person / Time
Site:	Davis Besse
Issue date:	02/27/1989
From:	Shelton D TOLEDO EDISON CO.
To:	Davis A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
REF-PT21-89-042-000 NP43-89-001, NP43-89-1, PT21-89-042-000, PT21-89-42, NUDOCS 8903090024
Download: ML20235U029 (2)

Text

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TOLEDO

%ss EDISON A Centenor Energy Company Docket No. 50-346 DONALD C. SHELTON Vce Presde1t-Nuclear

{419)P49 2300 License No. NPF-3 CCN No. DSS-89-15057 NP43-89-001 February 27, 1989 Mr. A. B. Davis, Regional Administrator United States Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 60137 Subj ect: 10CFR Part 21 Report Velan Maintenance Manual VEL-FBBH for 2 1/2" - 24" Forged Bolted Bonnet Gate and Globe Valves and Bolted Cover Check Valves i

Dear Mr. Davis This letter is to serve as the five-day notification of a 10CFR Part 21 defect which was identified by the Toledo Edison Company in a conversation with your Region III Office on February 22, 1989.

Toledo Edison used the vendor manual noted in the subject title as the basis for maintenance of its Velan Valve Corporation rising stem valves at the Davis-Besse Nuclear Power Station. The recommended dry film lubricant has been used on these motor operated valves since 1986. Investigation into signs of degradation in one valve in the area of the valve stem and stem nut, determined that this lubrication was not appropriate. The use of a dry film lubricant as recommended by the vendor manual significantly contributed to wear and increased motor operator torque requirements which if gone undetected could have led to motor operated valve failure.

The vendor manual recommended the use of a dry film lubricant, Holykote, on the valve stem / stem nut area. However, for motor operated valves the Holykote wears off sooner than expected causing higher friction in those areas. This is most likely due to high loads and the fast speeds of the motor operator.

Although a dry film lubricant is appropriate for high loads, it is not suited for fast speed applications. When questioned, the vendor now recommends the use of a wet lubricant, Chevron SRI, NLGI Grade 2 or equivalent. However, the vendor indicated that he has not nor does he plan to update his maintenance manual.

6 hbh $0 s

fil THE TOLEDO EDISON COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO, OHIO 43652

i Docket No. 50-346 License No. NPF-3 DSS-89-15057 Page 2 An inspection of rising stem valves in conjunction'with this event revealed twelve valves with noticeable degradation of the valve stem nut due to loss of lubricant. None of the valves were judged incapable of performing their intended safety function. This is due to the large margins above required thrust values to which motor operated valves were set up. The lubrication manual was revised to allow use of Chevron SRI, and relubing was completed for those that required it. Therefore, there is no immediate concern at Davis-Besse of these motor operated valves due to lubrication.

This report satisfies the requirement for written notification within five days of determination of a defect.

Sincerely w b DCS/JCS/plg cc: DB-1 NRC Resident Inspector