ML20086F728
| ML20086F728 | |
| Person / Time | |
|---|---|
| Site: | Robinson  |
| Issue date: | 01/27/1975 |
| From: | Utley E CAROLINA POWER & LIGHT CO. |
| To: | Knuth D, Moseley N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II), US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20086F733 | List: |
| References | |
| AO-50-261-75-1, NG-75-113, NUDOCS 8401040625 | |
| Download: ML20086F728 (3) | |
Text
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V Carolma Power & Light Company January 27, 1975 Files NG-3513 (R)
Serial: NG-75-113 NG-3514 (R) 50-261 ts Mr. Norman C. Moseley, Director kh[)s
'T Directorate of Regulatory Operations c3 J1. ) I ly U. S. Atomic Energy Commission h
Region II, Suite 818 p-_
JAN 3119756 -10 230 Peachtree Street, N. W.
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Atlanta, Georgia 30303 "l$$fyM L
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Mr. Donald Knuth, Director Directorate of Regulatory Operations 4
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Office of Regulation U. S. Atonic Energy Commission Washington, D. C.
20545
Dear Sirs:
H. B. ROBINSON UNIT NO. 2 LICENSE NO. DPR-23 FAILURE OF "A" BORIC ACID TRANSFER PUMP In accordance with 6.6.2.a of the Technical Specifications for H. B. Robinson Unit No. 2, the attached Abnormal Occurrence Report is submitted for your information. This report fulfills the requirement for a written report within ten days of an Abnormal Occurrence and is in accordance with the format set forth in Regulatory Guideline 1.16.
Yours very truly, E.
Utley Vice-President Bulk Power Supply JBM:me Attachment cc: Mr. N. B. Bessac Mr. W. E. Graham Mr. J. B. McGirt Mr. D. V. Menscer Mr. D. B. Waters
} } r, 040104062S 750127 PDR ADOCK 05000261 S
PDR 336 Fayetteville Street. P. O. Box 1551. Raleigh, N. C. 27602 4-a
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o ABNORMAL OCCURRENCE REPORT 1.
Report No.
50-261/75-1 2a.
Report Date January 22, 1975 2b.
Occurrence Date January 14, 1975 3.
Facility H. B. Robinson Unit No. 2 Hartsville, South Carolina 4.
Identification of Occurrence Failure of "A" Boric Acid Transfer Pump constituting an abnormal occurrence as defined in Section 1.8.d of the Technical Specifications.
5.
Conditions Prior to Occurrence The plant was operating at 100% nuclear power with 701 MW net electrical output.
"A" Boric Acid Transfer Pump was lined up to recirculate the Boron Injection Tank and "B" Boric Acid Transfer Pump was lined up to the boric acid blender.
6.
Description of Occurrence At 0940 hours0.0109 days <br />0.261 hours <br />0.00155 weeks <br />3.5767e-4 months <br />, "A" Boric Acid Transfer Purp was found to be tripped.
The pump was known to be running five minutas earlier. The thermal overload, at the breaker, was reset. However, subsequent testing re-vealed no discharge pressure with the motor running.
"B" Boric Acid Transfer Pump was test operated satisfactorily and "A" pump was removed from service.
7.
Designation of Apparent Cause of Occurrence Inspection of the pump and motor showed that the shaf t had failed in the vicinity of the impeller keyway. The only additional damage to the unit was the scoring of the stator liner. This is believed to have re-sulted after the shaft failure and caused the circuit breaker trip.
8.
Analysis of Occurrence Upon determination that "A" Boric Acid Transfer Pump was inoperable, "B" Boric Acid Transfer Pump was tested and its operability was verified.
Plant safety was, therefore, not jeopardized, and no limiting condition of operation was violated. No personnel injuries, undue exposures, re-leases of radioactive materials, or threat to the public health and safety resulted from this occurrence.
O O
9.
Corrective Action "A" Boric Acid Transfer Pump was replaced with a spare pump, test operated satisfactorily and returned to service at 0103 hours0.00119 days <br />0.0286 hours <br />1.703042e-4 weeks <br />3.91915e-5 months <br /> January 15, 1975. A replacement pump, Model GVH-10K, has been recommended by the pump vendor and is on order. Additionally, the G. E. 20K stub shaf t modification, referenced in previous reports, is being pursued in an effort to alleviate the recurring shaft breakage problem in the keyway area.
10.
Failure Data August 15, 1973 Crane Chempump Model G. E. 20K broken shaft near keyway.
December 4,1973 Crane Chempump Model G. E. 20K broken shaf t near keyway.
March 20, 1974 Crane Chempump Model G. E. 20K broken shaft near keyway.
August 8,1974CraneChempumpModelG.E.20Kbrokenshaftnearkeyway.
August 26, 1974 Crane Chempump Model G. E. 20K broken shaft at rotor (pump end).
December 4,1974 Crane Chempump Model G. E. 20K broken shaf t at rotor (pump end).
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