ML20086K281

Environ RO 74-2:on 740705,cooling Tower Inoperable for Period in Excess of 48 H.Caused by Excessive Vibration. Vibration Readings Taken to Determine Applicability of Present Motors

ML20086K281
Person / Time
Site:	Peach Bottom, 05002787
Issue date:	07/15/1974
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Giambusso A US ATOMIC ENERGY COMMISSION (AEC)
References
RO-74-2, NUDOCS 8401260418
Download: ML20086K281 (3)

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PHILADELPHIA ELECTRIC COMPANY 5 th 4.* ' 9 [:,.

2301 MARKET STREET '\

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PHILADELPHIA. PA.19101 A k ) 2 1 ?p O J J

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q$jj{i{m, , .: j July 15, 1974 b'  ?

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Mr. A. Giambusso j Deputy Director of Reactor Projects United States Atomic Energy Commission Directorate of Licensing 50-277 -

j Washington, DC 20545

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Dear Mr. Giambusso:

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Subject:

Environmental Deviation .

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The following deviation was reported by telephone to Mr. Eldon Brunner, A.E.C. Region I Regulatory Operations Offico,on July 5, 1974.

In ace ~da~ e with Ye:tien '.8!.2.A ef the Envir =ent:! Technic ! Sp :i-fications, Appendix 0 of DPR-44 for Unit 2 Peach Bottom Atomic Power Station, the following report is being submitted to the Directorate of Licensing as an Environmental Deviation. y

Reference:

License Number DPR-44/56 7 Environmental Technical Specification j Appendix B, Section 2.1 'j Report No.: 50-277/278-74-2 Repor.t Date: July 15, 1974 Deviation Date: July 5, 1974 Facility: -Peach Bottom Atomic Power Station j Units 2/3 8 R. D. 1, Delta, Pennsylvania 17314 f 1-k.

Identification of Deviation:

6 h One inoperable cooling tower for a period in excess of 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />. 4

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Conditions Prior to Deviation:

l Unit 2 operating at.approximately 90% power. Unit 3 shutdown  ;

during initial fuel loading 7 , j g g < d'y , ej ~

7 L DN O } n YSEN1'RE 6I ,

Mr.. A. Siambusso July 15, 1974 "

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i l Description of Deviation:

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-t The "B" cooling tower was inoiserable for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. An in- ~

o operable cooling tower in excess of 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> is classified by Appendix B '!

as an environmental deviation. The bases of Section 2.1 states that l ten of the eleven cooling tower fans must be operable in order' to con- l sider the cooling tower operabic. In t'is instance, only nine of the cleven fans of the "B" cooling tower were operable. .{

3 Cn July 3, 1974, the "J" fan motor on the "B" cooling tower experienced high vibration and was removed from service. The loss of i ^[

this motor reduced to nine the number of cooling tower fans in service.

This motor.was immediately sent to.a local service shop for recondition-ing. It was returned on July 5,1974, and reinstalled, but failed to  !,

operate during a: restart attempt. Investigation revealed a loose con- j nector lug on one of the motor leads. This lug was replaced and the 1 motor operated. After 50 minutes of operation the circuit breaker l tripped. The tripping was due to a defective breaker. A spare breaker }

was. installed and the motor returned to service. The "J" fan of the i "B" cooling tower was successfully returned to service on July 6,1974 (3:30 p.m.) . The return of this fan returned the "B" cooling tower 3 u.J to an operable status. It.should be noted that nine of the eleven fans were operable during this entire period of' time.

Designation of Apparent Cause of Deviation:

The cooling tower motors have been experiencing vibrations fW 1

.slightly in excess of that reccanended by the motor manufacturer. The cooling tower manufacturer has indicated that the vibrations measured are acceptable. During the week of July 1, 1974, three cooling tower motors were removed from service and sent to the manufacturer's shop j1 for rework. Inspection disclosed that two motors failed because of J excessive vibration and one f ailed because of what appeared to be a l lightning strike.  !

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s Anaylsis of the Deviation:

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. All three cooling tower pumps remained in service during the entire period of time. The small reduction in cooling capacity caused j by three of the thirty-three fans being inoperabic did not significantly  ;

affect the discharge temperature from the discharge structure. There- i fore, no significant environmental effect is associated with this de-viation. 4 l

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LJ ) j Mr. A. Giambusso i

,'Jul,y 15, 1974 Page 3 j i i

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C+:rrective Act ion:

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As noted above, repair s are being expedi ted to the motors l which failed in service. Additionally, vibration readings have been j trken on all other motors. The cooling tower and motor manufacturers j hrve been asked to aid in this investigation in an ef fort to determine I the applicability of the present motors for this service. {

Very truly yours, .

1 j

/e ( . 'n u i M. )/. Cooney ,p. l Ass't Gen'1 Superintendent Generation Division f

cc: Mr . J. P. O'Reilly Director, Region i g United States Atomic Energy Conmission  ;

631 Park Avenue "-

King of Prussia, FA 19406 rv e .

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