IR 05000528/1987026
| ML17300B022 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 08/14/1987 |
| From: | Mccullough M, Pate R, Richards S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML17300B021 | List: |
| References | |
| 50-528-87-26, NUDOCS 8708310103 | |
| Download: ML17300B022 (5) | |
Text
U. S.
NUCLEAR REGULATORY COMMISSION GI i
Report No:
50-528/87-26 Docket No:
-
50-528
..License No:
. NPF-41 Licensee:
Arizona Nuclear Power Project P. 0.
Box 52034 Phoenix, Arizona 85072-2034
~Fili i:
Pi i i i I
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Ins ection Conducted:
Inspectors:
July 15, 987 through July 17, 1987 ate, e
,
eactor a ety rane c u oug
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ngine ng i e te igne 8-iI 8 l ate gne ic ard
,
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ection D
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~Summar:
Ins ection on Jul 15, 1987 throu h Jul
1987 Re ort No. 50-523/87-26
'i Areas Ins ected:
A special reactive inspection on the mechanical seal failure on ow pressure safety injection pumps.
Inspection procedure 93702 was used for this inspection.
'Results:
Of the areas inspected, no violations were identified.
87083l0103 8708i4 PDR ADOCK 05000528
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DETAILS Persons Contacted
- J
- R.
- I
- T
- W.
- L E.
B.
T.
R.
Bynum, Plant Manager Baron, Commitment Supervisor, Compliance Zeringue, Manager, Technical Support Shriver, Manager, Compliance Simko, Supervisor, Operations Engineering (Mechanical)
Souza, Assistant Director, guality Assurance/guality Control Gouvier, Senior'lectrical Engineer, Environmental gualifications Kuntz; Engineer, Combustion Engineering Hall, Engineer, Operations Engineering Papworth, Manager, Operations. Engineering
- Attended exit meeting on July 17, 1987.
Low Pressure Safet In ection Pum Seal Failure On July 4, 1987, with the Unit I reactor in Mode 4, the low pressure safety injection (LPSI) "A" pump tripped from a motor overcurrent condition.
The "A" pump had been placed in service on July 2, 1987, when the "B" LPSI pump was placed in standby due to excessive pump seal-leakage.
At the time of the LPSI "A" pump trip, a smoke alarm had been received from the LPSI "A" pump room.
However, investigation revealed that no fire had occurred.
Following the pump trip, the LPSI "B" pump was placed into service and the reactor was cooled until it reached Node 5.
Once the reactor was placed in Node 5 following the "A" pump trip, the LPSI "B" pump was shut off and the Containment Spray (CS)
"B" pump was placed in shutdown cooling mode.
The "B" LPSI pump was estimated to be leaking at a rate of approximately I gpm on July 4, 1987.
On July 17, 1987, the last day of this inspection, the LPSI "B" pump was being disassembled in order to determine what caused the leak.
An inspection of the "A" LPSI pump mechanical seal was completed by the licensee on July 10, 1987.
The shaft packing "0-ring" was found swol,len but pliable.
At the time of the inspection, the licensee stated that the two remaining "0-rings" were not swollen.
Both the tungsten-carbide rotating seal face and the stationary carbon seal face were worn and chipping had occurred on the face of the inner diameter of the stationary seal..
The licensee believes that the motor failure was a direct result of the pump seal failure.
The failed "A" LPSI pump "0-ring" has been sent to Westinghouse for chemical analysis.
The licensee believes that the most probable cause of the "0-ring" swelling is due to a chemical reaction with some type of solvent.
However, at this time, they are still pursuing heat degradation as a possible failure mechanis As a part of this analysis, the licensee will be autoclaving a
new
"0-ring" and an "0-ring" from the Uriit 3 containment spray pump believed to have been treated with a chemical solvent called "Enviroguard", to observe heat degradation effects.
A new "0-ring" was sprayed with
"Enviroguard" and it swelled overnight.
Inspection of the LPSI "A" pump motor bearing by the licensee revealed the lower oil reservoir to be low on oil and the oil contaminated with a black foreign substance.
An analysis of the oil revealed the black.substance
.to be magnetite, a form of iron oxide.
Based on the preliminary analysis of seal failure of the Unit 1 LPSI pump, a justification for continued operation was submitted for Unit 2 on July 13, 1987.
The licensee found no evidence to indicate that an undesirable lubricant or solvent was used in assembly of the Unit 2 LPSI or CS pumps.
Additionally, water slingers have been installed on all Unit 2 LPSI and CS pump shafts to prevent water from leaking into the lower motor bearing in the event of a seal failure.
Maintenance procedures have been modified to include instructions prohibiting use of any type of petroleum based lubricant or solvent on the LPSI or CS pumps.
Disassembly of the Unit 3 CS pump revealed degraded
"0-rings" in the mechanical seal.
All three "0-rings" were swollen, and one of the
"0-rings" smelled like orange peel, leading the licensee to believe the most probable cause of the degradation to be the solvent "Enviroguard",
which also smells like orange peel.
These "0-rings" are also being sent to Westinghouse for chemical analysis.
Since the licensee's investigation of the event is not complete and there are several unanswered questions, this is an unresolved item.
(87-26-01)
N The 'inspectors met with licensee management representatives denoted in paragraph 1 on Ju1y 17, 1987.
The scope of the inspection, observations and findings as noted in this report were discusse I t