ML20245K717

Special Rept 89-03:on 890330,emergency Diesel Generator a Declared Inoperable Due to Cooling Water Leaking from Exhaust Valve Cooling Water Jumper O-rings on Cylinder 8 Into Rocker Arm Lube Oil Reservoir.Jumpers Replaced

ML20245K717
Person / Time
Site:	Callaway
Issue date:	05/01/1989
From:	Blosser J UNION ELECTRIC CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
89-03, 89-3, ULNRC-1997, NUDOCS 8905050145
Download: ML20245K717 (4)

Text

_ . _ _ _ _ _ _ _-_. _ _ _ _ _ _ _ _ - - _ _ - _ _ _ _ _ _ _ _ - _ _ _ _ _ _ _ _ . _ _ - _ _ _

l'

%> {Jg,9y

.Etecraic a

Callaway Plant May 1, 1989' l

1 l' U. S. Nuclear Regulatory Commission l Document Control Desk Washington, DC 20555 ULNRC-1997 Gentlemen:

DOCKET NUMBER 50-483 CALLAWAY PLANT UNIT 1 FACILITY OPERATING LICENSE NPF-30 SPECIAL REPORT 89-03 INVALID DIESEL GENERATOR 'A' FAILURE DUE TO WATER LEAKING FROM THE EXHAUST VALVE COOLING JUMPERS INTO THE ROCKER ARM LUBE OIL RESERVOIR The enclosed Special Report is submitted pursuant to Technical Specification (T/S) 4.8.1.1.3 concerning the invalid failure of Diesel

' Generator (D/G) 'A' due to a leaking 0-ring on the exhaust valve cooling water jumpers which allowed water to leak into the rocker arm lube oil reservoir.

.. D. Blosser Manager, Callaway Plant aw9 TPS/MKD:jlh Enclosure cc: Distribution attached i

S C

' \

Mading Aakkess P.O. Box 6 4 Fulton, MO 65251

u i cc distribution for ULNRC-1997 i

Mr. A. Bert Davis Mr. Thomas Alexion (2 copies)

Regional Administrator Office of Nuclear Reactor Regulation i U.S. Nuclear Regulatory Commission U. S. Nuclear Regulatory Commission Region III Mail Stop 13-E-21 799 Roosevelt Road Washington, D.C. 20555 Glen Ellyn, IL 60137 American Nuclear Insurers Mr. O. Maynard c/o Dottie Sherman, Library Wolf Creek Nuclear Operating Corp.

The Exchange Suite 245 P. O. Box 411  ;

270 Farmington Avenue Burlington, KS 66839 Farmington, CT 06032 Mr. Merlin Williams Manager, Electric Department Supt. of Regulatory Quality &

Missouri Public Service Commission Administrative Services P. O. Box 360 Wolf Creek Nuclear Operating Corp.

Jefferson City, MO 65102 P. O. Box 411 Burlington, KS 66839 Records Center.

Institute of Nuclear Power Operations Mr. R. W. DeFayette Suite 1500 Chief, Project Section 3A 1100 circle 75 Parkway U.S. Nuclear Regulatory Commission ,

Atlanta, GA 30339 Region III 799 Roosevelt Road NRC Resident Inspector Glen Ellyn, IL 60137 D. F. Schnell (400)

G. L. Randolph  ;

R. P. Wendling (470)

J. V. Laux A. C.'Passwater/D. E. Shafer/D. J. Walker (470)

G. A. Hughes Z170.05 (QA Record)

Z40SR (Z170.09 Commercial Record)

M. S. Evans M. E. Taylor H. Wuertenbaecher, Jr. (100)

S. L. Auston (470)(NSRB)

S. J. Bellers/D. R. Oelrichs E210.01 Z40ULNRC A160.761 N. Date (Sandra Auston) (470) l l

l

i SPECIAL REPORT 89-03 INVALID DIESEL GENERATOR 'A' FAILURE DUE TO WATER LEAKING FROM THE EXHAUST VALVE COOLING JUMPERS INTO THE ROCKER ARM LUBE OIL RESERVOIR on 3/30/89, at 0430 CST, emergency diesel generator (D/G) 'A' was declared inoperable due to cooling water leaking from the exhaust valve cooling water jumper 0-rings on cylinder #8 into the rocker arm lube oil reservoir. This is an invalid failure which is reported per Technical Specification (T/S) 4.8.1.1.3.

This condition was discovered when the rocker arm lube oil reservoir high-high Jevel alarm sounded. Approximately 1) gallons per hour of jacket water was estimated to be leaking into the rocker arm lube oil reservoir.

The rocker arm lubrication system is designed to collect all the oil which has been pumped to the rockers and return that oil to the rocker arm lube oil <

reservoir. From the rocker arm lube oil reservoir, the oil is pumped through paper element filters back to the rockers.

Given this condition, upon an D/G engine start, the rocker arm pump woul' have begun pumping the water in the rocker arm lube oil reservoir through the i filters. This amount of water would swell the filter elements stopping all i flow. The rocker lube oil pump has an internal relief valve which will relieve back to the pump suction. No oil would be delivered to the rockers.

In this mode of operation, the D/G will start and load as usual, and could run for approximately one hour without failing. Eventually, however, the rockers would seize and the D/G would fail. The engine could not be relied upon to perform its safety function.

The 0-rings were found to be hardened, allowing the water to leak by.

The leaking 0-ring on the exhaust valve cooling jumper was replaced. The rocker arm reservoir was drained and filled with appropriate lubricant. All remaining exhaust valve cooling jumper 0-rings, on both D/G 'A' and 'B', were j replaced. An Emergency Diesel Generator Reliability study is currently being l undertaken. Part of the scope is to enhance the installation duration for engine 0-rings. Procedure MSM-KJ-QK001, " Emergency Diesel Generator  ;

l Inspection", will then be revised to reflect the appropriate duration.

The D/G 'A' was declared operable at 0930 on 3/31/89. The D/G was  ;

unavailable for 29 hours3.356481e-4 days <br />0.00806 hours <br />4.794974e-5 weeks <br />1.10345e-5 months <br />. T/S 3.8.1.1 action statements were satisfied. I Since this failure did not occur during a test (valid or invalid), and {

therefore is not a valid failure, the surveillance test interval of T/S Table l 4.8-1 is not affected. This position is consistent with Regulatory Guide 1.108.C.2.e.

. \

l l

4

i

.o The starting history of D/G 'A' as of this report date is summarized as l follows:

l No. of No. of Failures No. of Failures Valid Tests During Valid Tests During Invalid Tests l

l l' 91 3* 6#

• Special Reports 84-02 6 87-10, LER 87-002 l # Special Reports 85-01, 85-02, 85-07, 86-01, 89-02 Surveillance tests are currently performed at least once per 31 days for D/G

'A'. This is in conformance with the schedule in T/S Table 4.8-1 which requires a test interval of not more than 31 days if the number of failures in the last 20 valid tests is one or less or the number of failures in the last 100 valid tests is four or less.

l I

_ _ _ - _ . - - - _ - _ - _ _ _ _ - _ _ - _ _ _