05000280/FIN-2012002-01
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Finding | |
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Title | Operability Determinations Questioned When the 1B Charging Pump Lube Oil Exhibited Foaming |
Description | During the nightshift on January 25, 2012, operators noted a more than usual level of foam present in the main gearbox oil sight glass on the running Unit 1 charging pump (1-CH-P-1B). This charging pump had been in service for approximately four and a half days following maintenance to the discharge check valve. A Condition Report (CR) was submitted and the licensees immediate operability determination (IOD) concluded that the pump remained operable because all pump parameters (e.g., bearing temperature, lube oil pressure, and pump flow rate) were normal. Later on dayshift of that same day, operators discovered that the foaming had gotten worse and now covered the entire sight glass with no oil level visible. Operators added one gallon of oil, but the oil level was still not visible and could not be determined. The pump was immediately shutdown based on a recommendation from engineering personnel who were present at the time. Another CR was written for this event and the IOD also declared the pump operable. The inspectors reviewed the issue and associated documentation on January 30 and found that the pump had remained secured and was considered operable since January 25. No actions had been taken or assigned from the previous CRs, no answers to the open questions were documented, and the CR had been closed to a work order that was still in a planning stage. The inspectors questioned the documented IOD, its lack of a technical basis for operability, and requested answers to the open questions. The next day, after further challenges from the inspectors, the licensee decided to run the pump again to see if foaming would occur immediately; an indication that air was intruding into the system. The pump was started with engineering personnel present and after approximately 30 seconds the foaming appeared and the sight glass was again full of foam. The pump was stopped again and Engineering confirmed that air intrusion was occurring. The licensee still maintained the pump was operable in this condition; however their IOD lacked a justifiable technical basis for that conclusion. On February 1, 2012, the inspectors challenged the conclusions of the operability determinations again and the licensee agreed that they did not have a proper technically justifiable basis to call the pump operable. They declared the pump inoperable and entered the applicable 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Technical Specification (TS) Limiting Condition for Operation (LCO). The licensee subsequently replaced the oil with new oil and also sealed all piping connections in the charging pump lube oil system. The pump was returned to service on February 4 and the air intrusion and foaming did not recur. The inspectors require additional information, including the licensees pending past operability justification, to determine an appropriate performance deficiency. This issue is identified as URI 05000280/2012002-01, Operability Determinations Questioned When the 1B Charging Pump Lube Oil Exhibited Foaming. |
Site: | Surry |
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Report | IR 05000280/2012002 Section 1R15 |
Date counted | Mar 31, 2012 (2012Q1) |
Type: | URI: |
cornerstone | Mitigating Systems |
Identified by: | NRC identified |
Inspection Procedure: | IP 71111.15 |
Inspectors (proximate) | W Loo J Austin J Nadel M Speck S Sanchez G Mccoy R Clagg J Stewart G Kolcum J Sowa D Millsj Nadels Sanchez G Mccoy A Sengupta |
INPO aspect | |
Finding closed by | |
IR 05000280/2012004, IR 05000280/2012502 (2 November 2012, 2 November 2012) | |
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Finding - Surry - IR 05000280/2012002 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Surry) @ 2012Q1
Self-Identified List (Surry)
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