ML20011A989

Deficiency Rept SD-370/81-08 Re Lubricant Leakage from Limitorque Valve Operator,Initially Reported 810921.Caused by Operator Being Oriented W/Limit Switch Compartment Facing Vertically Down.Operator to Be Rotated

ML20011A989
Person / Time
Site:	Mcguire
Issue date:	10/21/1981
From:	Parker W DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
10CFR-050.55E, 10CFR-50.55E, SD-370-81-08, SD-370-81-8, NUDOCS 8111030476
Download: ML20011A989 (3)

Text

, _ - _ _ _ _ _ . _ _ -. _ .. . _ __ _ _ _

l e

e DUKE PoWEH COMPM a b 'gg E  ?.

Powsa Dunamo W7 Eg O <

422 Sourn Cuencu STurr.T. CHAHWTTE, N. C. 28242 ' ' G r- ,

01 gU  %[

WI L LI A M O. PA R et ER, J R.

27

,,/,'$ ",*o'o'c',",'

, o ,

October 21, 1981 Y"N[,"l'.o's O

Mr. James P. O'Rollly, Director ff C U. S. Nuclear Regulatory Commission > {j Region II . $-i gO 101 Marietta Street, Suite 3100  ;

u.s. V 0 2 198 5 Atlanta, Georgia 30303

(

Re: McGuire Nuclear Station ,

Unit 2 47 )'

Docket No. 50-370 . '

Dear Mr. O'Reilly:

Pursuant to 10 CFR 50.55e, please find attached Significant Deficiency Report SD 370/81-08 concerning lubricant leakage from a LIMITORQUE va'1ve operator.

V y truly yours, C ~

gA> ._ m . . Xq.

William O. Parker, Jr.

GAC/smh Attachment ec: Director Ms. M. J. Graham Office of Inspection & Enforcement NRC Resident Inspector U. S. Nuclear Regulatory Commission McGuire Nuclear Station i Washington, D. C. 20555 e

f &0 s

/ /.

KOhoo$fhn PDR

_ _ _ _ _ _ _ - - _ _ _ _ _ _ _ _ _ _ _ _ _ . - _ _ -_ - _ ___ J_ _l

. . m __ _

4 McGuire Nuclear Station l

, Report No,.: SD-370/81-08 l

Report Date: October 21, 1981 I l

Facility: McGuire Nuclear Station, Unit 2 Identification of Deficiency: Valve 2RN86A. Limitorque Operator; Lubricant leak-age into limit switch compartment.

Description of Deficiency:

On September 21, 1981, Mr. W. O. Henry and Mr. E. W. Fritz advised Mr. A. Ignatonis, NRC Regien 11 office of the following deficiency.

During inspection of the motor operator on valve 2RN86A (Limitorque SML-000-57 for limit switch alignment, oil was found in the limit switch compartment. The valve operator was orientated such that the limit switch compartment was facing vertf-cally downward. Gear case iubricant had leaked into the limit switch compart-ment causing damage to control wiring insulation such that valve operation would be questionable.

This problem resulted from the valve operator be' g oriented with its limit switch compartment facing vertically downward. In this andition, gear case grease can stratify and oil may leak into the limit switch compartment. Contro) wiring in-sulation is not compatible with this oil and after exposure for six months to a f year, insulation will swell and start cracking. The wiring found in 2RN86A was swollen to about 150% original dimensions, i

~

Several factors are required for oil to leak into the limit switch compartment.

First, the valve operator must be oriented with the limit switch compartment fac-ing downward (an orientation not recommended by Limitorque). Then, the operator must remain idle (unoperated) for long periods of time (six montsh to a year) to allow the grease to stratify. Finally, actual oil leakage into the limit switch compartment is dependent on the seals betreen the limit switch mechanism and the operator gear case. If the tolerances of these seals are large enough (but still within manufacturing linits), then oil leakage may occur.

Analysis of Safety Implication: Consequences of the failure of valve 2RN86A to operate could result in loss of cooling water to one_ train of the Component Cool-ing System which supplies cooling water-to a number of safety-related systems in-cluding the Residual Heat Removal System Heat Exchanger.

l Corrective Action: Damaged wiring will be replaced in 2RN86A and the operator:ro-tated such that the limit switch compartment no longer faces vertically downward.

4 s-4 J

Corrective Action Cont'd 1

All other Limitorque operators will be inspected for proper orientation and li-mit switch compartments on those facing vertically downward will be . examined for oil and wiring. damage. Any operators found to be in a questionable orientr. tion will be rotated such that the limit switch compartment no longer faces vertical-ly downward. This audit and inspection was completed on October 9, 1981 for Mc-Guire Unit 2.

All Limitorque operators on Unit 1 have been inspected for orientation and wiring damage in those with limit switch compartments facing downward. This audit was completed on September 11, 1981 and no damaged wiring was found. Re-orientation of operators on both units will be completed as scheduling allows, before Unit 2 fuel loading and before completion of the first refueling of Unit 1.

i J

d l

1-l 5

I I