IR 05000397/1992024
| ML17289A777 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 07/15/1992 |
| From: | Gody A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | |
| Shared Package | |
| ML17289A776 | List: |
| References | |
| 50-397-92-24, NUDOCS 9208110107 | |
| Download: ML17289A777 (7) | |
Text
Report No.:
Docket No.:
License No.:
Licensee:.
U.S.
NUCLEAR REGULATORY COMMISSION
REGION V
50-397/92-24 50-397 NPF-21 Washington Public Power Supply System P. 0.
Box 968 Richland, Washington 99352 Facility Name:
Washington Nuclear Project No.
(WNP-2)
Inspection at:
WNP-2 Site,- Benton County, Washington Inspection Conducted:
June 8 through 19, 1992 Inspector:
C. A. Clark, Reactor Inspector Approved by:
A. T. Gody Jr., Acti Chi f Engineering Section Da e Signed I
ns ection Summar
Ins ection Durin the Period of June 8 throu h 19 1992 Re ort No.
50-397 92-24
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(ISI), Inservice Testing (IST), and Maintenance activities.
Inspection procedures 62700, 73753, 73755, 73756 and 92701 were used as guidance for the inspection.
Results:
General Conclusions and S ecific Findin s:
The discovery by the licensee of inappropriate fasteners in motor
= operated valves did not appear to have received timely followup and corrective actions.
A Performance of licensee ISI activities were documented in Inspection Report No. 50-397/92-20.
Si nif'cant Sa'fet Matters:
None Summar of Violations:
None 0 en Items Summar
. There were two new unresolved items identified in Section 3 of this report.
9208110107 920715 PDR ADOCK 050003'P7 8'DR
DETAILS Persons Contacted a.
Washin ton Public Power Su
S stem b.
- L.-Harrold, Assistant Plant Manager
- T. Hoyle,'otor Operated Valve Program Lead R. Hoen, Materials and Inspection Manager
- D. Ramey, ISI Engineer
- G. Sorensen, Regulatory Programs Manager
- R. Rebring, Technical Manager D. Welch, Nondestructive Examinations (NDE) Supervisor actor Mutual Insurance D. Hoggarth, Authorized Nuclear Inservice Inspector (ANII)
c Other
- A. Gody, Acting Chief, Engineering Section
- R. Nease, NRC Resident Inspector
- D. Proulx, NRC Resident Inspector
- C. Sorensen, Senior NRC Resident Inspector The inspector also held discussions with other licensee and contractor personnel during the course of the inspection.
- Denotes those attending the exit interview on June 12, 1992.
aintenance Pro ram Im lementation 62700 A review of maintenance activities associated with safety related components was performed to ensure they conformed with licensee administrative requirements and standard industry practices.
A review of a sample of maintenance completed work packages, prior to operational testing, identified a concern with motor operated valves 'which is
'iscussed in section 4 of this report.
A review of a sample of work activities and current work procedures in use dui ing work this outage did not identify any-concerns.
No violations or deviations were identified in the areas reviewed.
Inservice Testin o
Pum s and Valves 73756 A review of various activities occurring in the Inservice Testing (IST)
area was performed to determine whether IST regulatory requirements and licensee commitments were'being met.
The inspector observed the following:
A. ~l-ih 1i i
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Program Hay 7, 1991, from the Office of Nuclear Reactor Regulation.
Revision 4 of the IST Program Plan was submitted to the NRC on December 3,
1991 for review, in licensee Letter GO-91-'20.
IST Procedures The inspector reviewed a sample of recently issued.ASHE Section XI Surveillance Procedures and found that the procedures appeared to contain additional clarification information, and instructions over previous procedures.
No concerns were identified during this procedure review.
oto 0 crated alves The inspector's review of a sample of
.
maintenance work packages identified that during current IST '
maintenance and testing activities, problems were identified with various motor operated valves (HOVs):
~
'Valve HS-V-19.
On April 29, 1992 Problem Evaluation Request (PER)
No. 292-379 identified that,
"During as left testing of HOV Operator HS-H0-19, the torque switch possibly failed to perform its design function.
The result of this malfunction led to the motor achieving a locked rotor condition.
Due to the over-thrusting of the actuator, all
,.four bonnet to actuator studs were stretched to the point where the torque thrust cell (TTC) was no longer flush with the bonnet seat (the TTC was mounted during testing).
An attempt was made to retorque the studs to the design requirement of approximately 18 ft/lbs, however, this attempt led to the shearing of one of the studs (bolts).
Impact:
had the stall condition occurred, with bolt failure, during power operations the valve would have been unable to perform its design function."
Valve MS-V-19 is a ASHE Code Class 1 Velan 3,inch flexwedge motor operated gate valve, used for containment isolation.
The licensee's recommended corrective action for this PER.
was in part, to "generate stall torque)thrust calculations to verify no damage was done to the actuator, stem, or valve....evaluate stud material....
The torque switch
'hould be inspected for mechanical wear or damage and replaced if"required.- Replace the damaged mounting -studs.
with a qualified grade of bolt or stud material."
On Hay 1, 1992 the Management Review Committee required that Maintenance Work Requests (HRWs)
be issued for inspection and repair of the valve (HS-V-19) and motor operator (HS-HO-19),
and that a failure analysis of the valve failure be performe ~,i
On Hay 1, 1992 licensee interoffice memorandum SS2-PE-92-0371 identified that the licensee had completed initial stall calculations and initial operator to valve yoke stud material examinations.
This memo indicated that the studs were supposed to be ASTH A574 with a minimum yield strength of 135 thousand pounds per square inch (KSI).
This memo also indicated that the installed studs were found to have a yield strength of 60 to 70 KSI. It appeared that SAE Grade 5 fasteners should have been installed in this application.
The inspector requested information from the licensee regarding:
(1) the results of the root'ause'analysis; (2)
the number of similar valves in the plant that could have non-Grade 5 stud material installed; (3) if there were any operational concerns with valves that could have non-Grade
stud material installed; and (4)
how the non-Grade 5 stud material was installed in valve HS-V-19.
At the time of the inspection, the licensee was still evaluating this problem.
The concern with the licensee's actions taken in response to the problems identified with valve HS-V-19 and operator HS-HO-19 is an unresolved item (50-397/92-24-01).
The.
inspector observed that, the licensee's initial response actions for this problem did not appear timely, since a
month had elapsed since the problem was identified.
~
Valve HPCS-V-23.
On June 10, 1992 PER 292-662 identified that while performing final torquing of the upper housing cover bolts on motor operator HPCS-H0-23, installed on valve HPCS-V-23, one of the 1 inch bolts became elongated and cracked.
Valve HPCS-V-23 is an ASHE Code Class 2 high pressure core spray 12 inch motor operated globe valve, used for containment isolation.
Limitorque maintenance update 89-1 identified two types of hardware used in the assembly of Limitorque housing covers and motors on the SHB series of actuators.
The grade of hardware employed was linked to the type of fastener.
Hex head cap screws SAE Grade 5 and socket head cap screws SAE Grade 8 (strength equivalent)
were -installed-during operator assembly.
Initial licensee
'erbal information identified that installation of non-Grade 5 fastener material may have been a factor in this fastener failure.
The licensee was evaluating if a Part
report would be issued on these as received non-Grade
fasteners.
The licensee was performing an investigation to identify how many valves could have the same non-Grade
fastener material installed and if there was a question
about the operability of any similar motor operator with similar fastener material.
The concern with the fastener failure on valve operator HPCS-NOV-23 is identified as an unresolved item (50-397/92-24-02).
No violations or deviations were identified in the areas reviewed.
Unresolved Item An unresolved item is a matter about which more information is required to ascertain whether it is an acceptable item, a deviation, or a violation.
xit eetin The inspector met with the licensee management representatives denot'ed in Section 1,
on June 12, 1992.
The scope of the inspection and the inspector's findings up to the time of the meeting were discussed.
At this meeting the inspector identifi'ed that he had obtained some information, and requested some additional information be sent to the regional office.
The inspector identified that this additional information would be'eviewed later in the region, with those findings documented in this report.
The available information was reviewed and the findings included in Sections 2 and 3 of this repor '
f