ML18010A639
| ML18010A639 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 04/30/1992 |
| From: | Schnebli G, Casey Smith, Taylor P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML18010A638 | List: |
| References | |
| 50-400-92-06, 50-400-92-6, GL-89-10, NUDOCS 9205190151 | |
| Download: ML18010A639 (28) | |
See also: IR 05000400/1992006
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UNITED STATES
NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTASTREET, N.W.
ATLANTA,GEORGIA 30323
Report No.. 50-400/92-06
Licensee:
Carolina Power and Light Company
P. O. Box 1551
Raleigh, NC 27602
- Docket No. 50-400
Facility Name:
Harris
1
License No. NPF-63
Inspection Conducted:
April 6-10, 1992
Lead Inspector:
P. Taylor
Inspectors:
.
C. Smith
Date Signed
C
DaeSi
d
+~G.
c
ebli
Others Contributing to This Inspection:
Date Signed
R. Cain, Idaho National Engineering Laboratory
Approved by:
F. Jape, Chief
Test Program Section
Engineering Branch
Division of Reactor Safety
Date Signed
SUMMARY
Scope:
This special, announced inspection examined the program developed in response to
NRC Generic Letter (GL) 89-10, "Safety-Related Motor Operated Valve Testing and
Surveillance."
The inspection was conducted
in accordance
with NRC Temporary
Instruction 2515/109, issued January 14, 1991.
9205190151
920506
ADOCK 05000400
8
Results:
In the areas inspected, violations or deviations were not identified.
The inspectors determined that the GL 89-10 MOV program was satisfactory at the
current stage of development.
Concerns were identified in some of the MOVprogram
areas.
The MOV program was also found to contain strengths.
The concerns identified involved licensee MOV program documents whose adequacy
willrequire further review.
In addition concerns similar to these are largely the result
of technological uncertainties regarding the predictability of MOV operation..These
uncertainties
should
be resolved
as
MOV data
is disseminated
throughout the
industry. The concerns and strengths identified for the Harris MOVprogram are listed
below:
CONCERNS
(1)
Present commitments require DP-Flow testing MOVs where practicable.
letter dated June 6, 1991 and discussions with engineers responsible for the
program indicate that selected
MOVs may not be in-situ tested
that are
practicable to be tested.
If MOV testing is discontinued the NRC should be
notified and technical justification provided (paragraph 3d).
(2)
The rate of loading effects had not been addressed
in MOV sizing and thrust
calculations.
Industry tests
have
shown
rate
of loading to yield non-
conservative
(ie lower) thrust values.
The rate of loading is planned to be
evaluated for those MOVs that are DP-flow tested.
Appropriate evaluation of
rate of loading should be documented for all MOVs in the program.
It is not
clear at this time what DP range will bound the rate of loading phenomenon
(paragraph 3c).
(3)
Static tests are planned during periodic testing to demonstrated MOVcapability
to perform under design basis conditions. It is not clear that static testing can
demonstrate
design basis capability because of the uncertainties between the
performance of MOVs under static and design conditions.
The licensee will
need to justify that the present periodic test methodology will demonstrate
MOV operability at design basis conditions (paragraph 3e).
(4)
MOV program procedures
do not require that "as found" periodic test
be
perform prior to conducting
any MOV preventive
maintenance.
This is
necessary
in order to properly evaluated existing MOV conditions, trends and
degradation
(paragraph 3e)
~
3
Other program procedures that are being changed and will require further NRC
review are:, TMM-406, Changes that will strengthen
the MOV operability
evaluations and onsite re'views of test results; PM-I0043, Changes that will
identify the use of equipment data base system'for torque switches and for
lirriit:switches in procedure
CM-l002 and changes
to PLP-112 which will
describe MOV test program activities and responsibilities (paragraph
3d and
3e).
(5)
The licensee, took exception to GL 89-10 recommendation
regarding MOV
mispositioning in their letter dated June 6, 1991.
The final disposition of this
" item remains to be determined and is under review by the NRC (paragraph 3a).
(6)
The
licensee
is using
a 0.40
locked
rotor power factor for AC MOV
calculations.
Higher locked rotor power factors have recently been published
by Limitorque.
The licensee should address the effects that the new power
factors have on MOV calculations
and corrections
applied as appropriate.
(paragraph 3.b).
STRENGTHS:
Engineers
responsible
for the
MOV programs
were
found
to
be
very
knowledgeable regarding ongoing MOV issues and state-of-the 'art regarding
diagnostic systems.
(2)
Involvement in industry groups is extensive, sometimes
in a leadership role.
(3)
The extend to which DP-flow testing has already been corn'pleted
and the
priorities and resources given to testing MOVs at the Harris Plant,
(4)
The programs that are in place for ensuring industry experiences
and vendor
information are incorporated into plant documents and training programs were
found to be very effective.
TABLE OF CONTENTS
Page
1.
BACKGROUND
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2.
INSPECTION PLAN .. ~.....
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3.
PROGRAM AREAS INSPECTED AND FINDINGS......... ~........
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a.
Scope of the Generic Letter Program..........
b.
Design-basis Review....... ~...
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c.
MOV Switch Settings
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d.
Design-basis Differential Pressure
and Flow Testing
e.
Periodic Verification of MOV Capability ... ~....
f.
MOV Failures, Corrective Actions, and Tending
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Schedule.......
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h.
Overall Administration of MOVActivities.......
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MOV Setpoint Control...
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Training
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Industry Experience and Vendor Information.....
Use of Diagnostics .................. ~...
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4.
= EXIT INTERVIEW
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APPENDIX 1 - PERSONS CONTACTED
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1 8
REPORT DETAILS
NRC Inspection of the Program Developed in Response to Generic Letter 89-10 at
the Harris Facility
Background
Generic Letter (GL) 89-10, Safety-Related
Motor-Operated Valve Testing and
Surveillance,
was
issued
June 28,
1989
and
requested
licensees
and
construction
permit holders to establish
a program to ensure that switch
settings for safety-related
motor-operated
valves (MOVs) and certain other
MOVs in safety-related
systems
are selected,
set and maintained properly.
Supplement
1 to GL 89-10 was issued June 13, 1990 to provide the results of
those public workshops.
Supplement 2 to GL 89-10 issued August 3, 1990,
stated that inspections of programs developed in response to GL 89-10 would
not begin until January 1, 1991.
Supplement 3 to GL 89-10 was issued on
October 25, 1990 and requested that boiling water reactor licensees evaluate
the capability of MOVs used for containment isolation in several systems.
In
addition all licensees
and construction
permit holders should consider the
applicability of the information contained in Supplement 3 and should consider
this information in the development of priorities for implementing the generic
letter program.
The NRC staff requested licensees to submit a response to the generic letter by
December 28, 1989. Carolina Power and LightCompany submitted a response
to the generic letter for its Harris Facility on December 27, 1989 and June 6,
1991.
In those
response,
CP5L indicated that it planned
to meet the
recommendations
of the generic letter and would comply with the 5-year
schedule (completion by June 28, 1994) for the Harris Facility.
2.
Inspection Plan
The
NRC
inspectors
followed
Temporary
Instruction
(Tl)
2515/109
(January 14,
1991),
"Inspection
Requirements
for Generic Letter 89-10,
Safety-Related Motor-Operated Valve Testing and Surveillance," in performing
this inspection.
The inspection focused on Part
1 of the TI which involves a
review of the program being established
by the licensee
in response
to GL 89-10.
Part 2 of the Tl, which involves
a detailed
review of program
implementation, was not performed. Implementation was examined only where
this aided in evaluating the program.
Program Areas Inspected and Findings
a 0
C
Scope of the Generic Letter Program
The scope of GL 89-10 includes all safety-related MOVs and other MOVs
"that are position-changeable
in safety-related piping systems.
Supplement
1 defined "position-changeable"
as any MOV in a safety-
related piping system
that can be inadvertently operated as a result of
an action in the control room.
The inspectors
reviewed
and discussed
the scope
of the GL 89-10
Program with licensee's
personnel
to ascertain
compliance with the
above GL recommendation.
The inspectors determined that the scope
of GL program consisted
of 116 MOVs.
Criteria used for selecting
- GL 89-.10 MOVs were delineated in Section 3.0 of Nuclear Engineering
Department Document No. Q9-MO-002, Revision 2. 'he licensee
in
their
response
dated
June 6,
1991,
stated
that
inadvertent
mispositioning of MOVs, initiated from the control room, in conjunction,
with an additional single active failure is beyond the current licensing
basis for CP&L plants..
The MOV program, therefore only considered
events that are within the current Iicensihg basis for Shearon
Harris
[Concern (5)].,
The inspectors. independently verified the accuracy of the GL program
scope by comparison of selected
MOVs shown on P&ID's with those
identified in the licensee's
GL 89-10 MOV List. The P&ID's used as the
basis for this review were the Component
Cooling Water System
(CCWS), Chemical and Volume Control System
(CVCS), Containment
Spray (CS) and Residual Heat Removal (RHR). Additional verification. of
the program scope was accomplished by reviewing selected
EOPs.
The
following EOPs
contained
required
operator
actions
for positioning
selected
MOVs during events.
These
MOVs were compared to the
licensee's
GL 89-10 MOV List to verify in'elusion in the program.
Procedure No. EOP-RPP-008,
SI Termination, Revision 4.
Procedure No. EOP-EPP-033,
Loss of AllAC Power Recovery with
Sl Required, Revision 4.
Procedure No. EOP-EPP-044.
Reactor Trip Response,
Revision 4.
All MOVs selected for review was determined to have been included in
the scope of the GL 89-10 Program.
No deficiencies were identified.
Design-Basis Reviews
Recommended
action
a
of
requests
the
review
and
documentation of the design basis for the operation of each MOV within
the
generic
letter program to determine
the
maximum differential
pressure
and flow (and
other factors)
expected
for both
normal
operations and abnormal conditions.
4
The inspectors reviewed the licensee's Motor Operated Valve Program
document
as
well as
other
documents
as
they
pertained
to the
development
of- design
basis'reviews.
Those
documents
included
09-MO-002;
"NED Scope
Document for work tasks
authorized
by
CPSL's Nuclear Facilities in response
to Generic Letter 89-10, Motor
Operated
Valves,"
(Rev; 2, May 31,
1991), AF-0029; ."Mechanical
Analysis and Calculations for 1AF-93," (Rev. 2, February 24, 1992), AF-
0031; "Mechanical, Analysis and Calculations for 1AF-143," (Rev.
1
January 31, 1992), Sl-0021; Mechanical Analysis and Calculation for
1CS-278," (Rev.-1 February 24, 1992), Sl-0023; "Mechanic'al Analysis
arid Calculations for 1SI-359," (Rev. 0, February 24, 1992).
Shearon Harris Nuclear Power Plant (SHNPP) determined the designbasis
differential pressure 'for each
MOV by reviewing their Final Safety
Analysis Report (FSAR), Design Basis Documents (DBDs), plant normal,
abnormal and emergency'perating
procedures.
Fluid temperature
and
'low were specified for design basis condition but was not included in
the review for determining the design basis differential pressure.
The
licensee engineers noted that there is no factor for flow or temperature
in the standard industry calculation forthrust. SHNPP intends to monitor
and record flow and temperature during the differential pressure test.
If
these parameters
are not the same as would be found during the actual
design basis differential pressure for which the MOV is designed, then
these
differences
would
have
to
be
reconciled
prior to
= the test
considered acceptable.
SHNPP used conservative assumptions
in determining their design basis
differential pressures.
In'ost'cases
pipe frictional losses
were not
included,
pumps
were considered
to be operating
at shutoff head,
elevational differences were not considered if it reduced the differential
pressure,
and the highest safety setpoint was used with the appropriate
amount of accumulation added to the setpoint.
However, the licensee
did not determine if valve mispositioning would cause the design basis
4
differential pressure to be larger.
SHNPP and CPSL stated
in their response letter to Generic Letter 89-10 (GL 89-10)
that valve mispositioning is beyond the design basis for
SHNPP'and
other CP8iL plants.
Valve mispositioning for
pressurized water reactor (PWRs) is currently under review
by the NRC staff.
SHNPP
reviewed
their documentation
on plant seismic
events
to
determine the'effects, if any, on MOV operation.
Licensee engineers
showed that seismic events for MOVs were considered
in the. original
.
design basis documents and the FSAR, and that these documents. would
bound any seismic event which could effect MOV performance.. The
inspectors discussed with licensee engineers the Limitorque Corporation
Technical
Update
¹92-01,
which
reviews
the
Kalsi
Engineering
Department '¹1707-C,. (Rev. 0, November 25, 1991).
The Limitorque
Updates included thrust rating increase for SMB-OOO, SMB-OO, SMB-O,
and
SMB-1 actuators
and section 4.5,included
seismic qualification
tests.
Licensee engineers indicated that the seismic qualification tests
and results were part of the thrust rating increase report and would'be
used when SHNPP used the study to increase actuator thrust ratings.
The inspectors did not identify any'actuators that had implemented the
Kalsi study during the inspection.
SHNPP performed-degraded
voltage calculations for each MOV in their.
program.
Documents
used for this analysis were, "Design Guide for
Electrical Evaluation of AC Power Motor-Operated
Valve." DG-V.67
(Rev. 2, April 1, 1992), "Design Guide for Electrical Evaluation of DC
Powered Motor-Operated Valves," DG-V.69 (Rev. 4, April 4, 1992), and
SHNPP
Design
Basis Document,
"Plant Electrical Systems,
Off Site
Power Systems, Generator, Exciter, Isolated Phase Bus Duct, Generator
and
Exciter Mechanical
Support
System,"
DED No. 202
(Rev.
0,
January 12, 1987).
The purpose of the calculations were to determine
the starting terminal voltage at degraded grid and accident
temperature'onditions
for MOVs in the program. These voltages were then used to
determine the amount of torque the MOV motor is capable of developing
during design
basis
conditions.
SHNPP
considered
elevated
cable
temperatures
by determining
what compartments
the cable
passed
through
and
then
used
the
worst
case
temperatuie
(highest
temperatures) for that compartment and applied it to the entire length of
the, cable.
Cable lengths and thermal overload (TOL) resistances
were
used in the calculations with a assumed
MOV starting power factor of
0.40 at locked rotor as recommended
by Limitorque.
The inspectors determine that Limitorque had recently published higher
locked rotor power factors than the 0.40 value
used
in electrical
calculations of AC MOVs. The licensee indicated that they were aware
of the new locked rotor power factors recommended
(telecon P. Taylor
Rll and 'M. Pugh, Nuclear Engineering Department April 30, 1992) by
Limitorque and were evaluating the information.
The incorporation of
Limitorque recommendations
in to design
guide
DG V.67, Electrical
Evaluation of AC Power MOVs will be reviewed during a subsequent
inspection [Concern (6)).
SHNPP
utilized TOL devices
to protect their MOVs during normal
operation.
However, during a safety system actuation SHNPP bypasses
their thermal overloads.
This was based
on the recommendations
of
The selection criteria for normal operation
included,
but was not limited to, ambient temperature
differences
between the MOV and the motor starter, motor full load amps, motor
service factor, relay trip time, and valve stroke time requirements.
Licensee personnel'were familiar with the possible degraded AC and DC
motor torque output due to MOVs being
located
in high ambient
temperature.
For DC MOVs, the licensee had used the recommendations
of Limitorque. For AC MOVs, the licensee had developed an on site plan
to be used.
The SHNPP plan reviewed plant documentation
in order to
determine the highest ambient temperature that will be seen by a given
MOV. Motor resistances
are recalculated based on the highest ambient
temperature.
With these new resistance values, licensee personnel then
recalculated the available AC motor torque.
Licensee engineers plan to
review Limitorque's high ambient temperature
findings when
made
available and will determine which method would best envelop their
MOVs.
SHNPP had reviewed the Generic Letter 89-10 issues concerning design
basis operating conditions for MOVs in their program.
The inspectors
concluded the licensee
had adequately
addressed
the area of design
basis
reviews
and
it
appeared
to
be
consistent
with
the
recommendations
of GL 89-10.
MOV Switch Settings
Recommended
action b of Generic Letter 89-10, requests licensees to
review, and to revise as necessary, the methods for selecting and setting
all MOV switches. (i.e., torque, torque bypass, limit, thermal overload)
6
The inspectors reviewed the licensee's documents for MOV sizing and.
switch
settings.
These
documents
included,
"Design
Guide
for
Limitorque Motor-Operated Valve Mechanical Evaluations," Design Guide.
DG-1.11,
(Rev. 4,
February 3,
1992)
and
calculations:
AF-0029;
"Mechanical
Analysis
and
Calculations
for
1AF-93,"
(Rev.
2,
February 24, 1992), AF-0031; "Mechanical Analysis and Calculations for
1AF-143," (Rev. 1, January 31, 1992), SI-0021; "Mechanical Analysis
and Calculations for 1SI-340," (Rev: 0, February 24, 1992) CS-0007;
"Mechanical
Analysis
and
Calculation
for
1CS-210,"
(Rev. -1,
January 28, 1992), CS-0016;.Mechanical
Analysis and Calculation for
1CS-278," (Rev. 1, February 24, 1992), SI-0023; "Mechanical Analysis
'nd
Calculation for 1SI-359," (Rev. 0, February 24, 1992). The licensee
had 116 MOVs in their program.
Of these 116 MOVs, 36 calculations
had been completed and undergone internal review.
The remaining 80-
calculations werestill considered to be in draft form until the internal
review had been completed.
The licensee's
engineers
performed the MOV calculations
using the
standard
industry equations for determining minimum required valve
thrust and torque.
For added conservatism,
SHNPP used a valve stem
coefficient of friction (COF) of 0.20 for calculating the minimum required
thrust value and a value of 0.15 to determine the maximum thrust valve.
SHNPP intends to verify their assumption
of COF through their test
program.
The licensee used a valve factor (VF) of 0.40 for gate valves
. and the mean
seat
diameter
in their MOV sizing calculations.
An-
exception to this methodology was with Westinghouse supplied valves.
Westinghouse supplied valve factors to SHNPP for We'stinghouse valves
which varied from 0.485 to 0.55. After reviewing industry data, SHNPP
engineers considered
a VF of 0.40 to be the average from the industry
data available to date.
A VF of 1.1 was used for globe valves.
The
licensee is planning to use the test results from insitu testing to validated
MOV calculation assumptions.
A margin of 15% is added
to the
minimum
required
thrust
to
account
for
diagnostic
equipment
inaccuracies
and torque switch repeatability.
The maximum actuator
thrust and torque rating is reduced by 10% to account for inertial effects
and diagnostic inaccuracies.
The inspectors noted that the 10% margin
may not be sufficient to bound diagnostic equipment inaccuracies, inertia
effects, and torque switch repeatability. The latest Limitorque Technical
Update (92-01) extending actuator thrust ratings.
Licensee engineers
stated, they would consider these effects if.they used the extended
thrust ratings for their actuators.
7
SHNPP replaces, or installs limiter plates. on their MOVs.
This action
is specified
in their procedures
RM-10020,
Rev. 3, and CM-10002, Rev. 4.
When it is necessary
to
increase the torque switch setting greater than the vendor
recommended
maximum, a design change notice (DCN) or
similar document is issued and an appropriate engineering
analysis
is performed.
The analysis
would considered
spring pack capability, degraded voltage performance, and
other factors to ensure
maximum actuator
and
thrust rating was not exceeded.
'A new limiter plate would
be ordered and installed.
SHNPP bypasses
the open torque switch for the MOVs.
The open
torque switch is placed back in service above the open limit switch
setpoint as a safety-feature
in case of limitswitch failure. Valves which
utilize the torque switch in the close direction have their torque switches
bypassed for 96% of travel and then the torque switch is placed in the
circuit for the last 4% of valve travel to ensure seating.
The licensee
had a very small population of valves which used the closed limitswitch
to stop motor operation.
The inspectors questioned the licensee if any
of their valves which used
the closed
limit switch to stop
motor
operation also had specified criteria for leakage.
The licensee responded
that- they did have some limit-close valves which do have specified
leakage criteria. However, licensee personnel stated that all the valves
which limit close and have specified
leaka'ge
criteria are of the
actuator type which utilizes an additional compensating
spring.
This
compensating spring allows setting of the limitswitch setpoint to ensure
hard seating of the valve has been accomplished.
SHNPP has investigated
the phenomena
of "rate of loading" (ROL).
SHNPP described this phenomena
as the difference in the value of thrust
indicated at torque switch trip under static conditions as compared to
the thrust value at torque switch trip under dynamic conditions.
SHNPP
personnel
stated
this phenomena
has
not been
observed
on site,
although the existence of ROL has been proven in several industry tests.
SHNPP plans to use the results of their diagnostic testing to determine
where
the condition applies
at their plant,
and to take
actioh
as
appropriate.
The inspectors were concerned that without a margin set
aside in the calculations forunknown phenomena,
switch settings may be set non-conservatively.
This could lead to valves
failing to operate
under design basis conditions.
Further, for valves
which cannot practicably be tested
in situ at design basis conditions,
SHNPP did not have in place a method to account for ROL that these
valves could experience.
Margins assigned
for unknown phenomena
8
based on dynamic test results should be included in the calculations for
these valves to ensure that torque switches are set conservatively and
to ensure that valves will function under design ba'sis conditions.
This
area will be reviewed during a future inspection [Concern (2)].
Design Basis Differential Pressure
and Flow Testing
Recommended
action c of the generic letter, requests licensees 'to test-
MOVs within the generic letter program in situ under their design-basis
differential pressure
and flow conditions.
If testing in situ under those
conditions is,not practicable, the staff allows alternate methods to be
used to demonstrate the-capability of the MOV. A two-stage approach
is suggested
for situations
where design-basis
testing
in situ is not
practicable and, at this time, an alternate method of demonstrating MOV
. capability cannot be justified. With the two-stage approach,
a licensee
would evaluate the capability of the MOV using the best data available
and then would work to obtain applicable test data within the schedule
of the generic letter.
CPSL MOV Program Plan (Q9-MO-001, Q9-MO-'002) and letters dated
December 27, 1989 and June 6, 1991 commit to in situ testing MOVs
under design basis conditions where practicable and baseline tests (static
conditions) of all MOVs in the program would also be performed.
The
June 6,
1991
CPSL
letter
indicated
that
a
preliminary review
is
underway which would delete MOV testing that are practicable to DP-
flow tests,
The exa'mples given were small gate and globe valves two
inches or less.
These would be grouped and a few of these MOV would
be differential pressure tested.
It is not clear how the licensee. will apply
tests
results to the similar non tested
MOVs in the group.
The
inspectors cautioned that the discontinuation of MOV testing that are
practicable
to test
is
a deviation from their present
commitment.
'herefore
NRC notification with appropriate technical justification should
be piovided. [Concern (1)].
The inspectors reviewed the following documents, which describes the
DP-flow testing program requirements and guidance:
Q9-MO-002,
Revision 2
dated,
May 31,
1991,
. NED
Scope
Document GL 89-10 MOVs Enclosure
1, MOV DP Test Program
Design
Guide
DG-1.12,
Revision
2 dated,
February 6,
1992,
Review and Reconciliation of MOV Diagnostic Tests
Technical Support Guide TSG-242, Revision 0 dated March 23,
1992,
Guidance
for Preparation
of MOV Engineering
Periodic
Tests
Technical Support Management
Manual, TMM-406 Revision
1
dated
January 28,
1992
Analysis
and
Trending
of
Performance
The inspectors found that the guidance provided in the aforemention
documents
address
MOV operability and
the
reconciliation of the
assumptions
(e.g
stem
factor,
valve factor)
used
in the
MOV's
torque/thrust calculations.
The SHNPP had performed in situ DP-flow
tests on 42 MOVs during refueling outage 3 (Spring 1991). The licensee
recently completed
the review and approval of the test results
and
reconciliation of torque/thrust calculation assumptions.
The inspectors
expressed
a concern with the significant length of time to complete the
review and approval of test results.
The licensee indicated that the
review/approval process would be completed in more timely manner.
In
addition the licensee
should consider
a more detailed review of test
results onsite by the Technical Support Group to ensure
MOV thrust
margins are adequate
and any MOV abnormality is addressed
prior to
returning the MOV/system to operation [Concern (4)].
Periodic Verification of MOV Capability
Recommended
action d of the generic letter, requests the preparation or
revision of procedures to ensure that adequate
MOVswitch settings are
determined and maintained throughout the life of the plant.
In Section
j of the generic letter, the staff recommends surveillance to confirm the
adequacy of the settings.
The interval of the surveillance is to be based
on the safety importance of the MOV as well as its maintenance
and
performance history, but is not to exceed 5 years or 3 refueling outages.
Further, the capability of the MOV is to Se verified if the MOV is
replaced,
modified, or overhauled to an extent that the existing test
results are not representative of the MOV.
The licensee's upper-tier program document number Q9-MO-001, GL 89-
10 MOV Program Specification, Revision 0, Section 11.0, established
requirements for'performing periodic diagnostic testing to identify MOV
degradations.
The frequency for performing periodic tests was given as
every 5 years or 3 RFO from the date of the initial baseline test or
differential test, whichever was performed later.
Site level procedures
numbers PLP-112, Motor Operated Valve Program; TMM-406, Analysis
and Trending of MOVPerformance and PM-I0043; Motor Operated Valve
'
10
Testing
and
Calibration,
collectively implement
these
requirements
delineated in the upper-tier program document. The inspectors identified
a
concern
with procedure
PLP-112
in that
the
program
controls
described
in paragraph
5.3 did not specifically address
periodic test
requirements.
Additional
programmatic
inadequacies
related
to
procedure
paragraph 6.0 was identified.
The inspectors
determined that the Equipment D'ata Base System
(EDBS) will be the
source of design basis information involving torque switch and limit
switch settings.
Lower-tier site
level procedure
PM-I0043, which
implements
periodic test activities involving torque switch settings,
needs to be revised to reflect the use of EDBS in this activity. Similarly,
procedure CM-I0002, A.C. Limitorque Calibration. Check and Stroking
will be revised to require limit switch settings to be obtained from the
EDBS. These items are identified as concerns that will be reinspected in
future MOV inspections [Concern (4)].
Discussion
with licensee
engineering
personnel
revealed
that static
diagnostic testing would be performed periodically to reverify design
basis capability of the MOVs within GL 89-10 program scope.
The
inspectors informed licensee management that the use of static testing
to verify continued capability of an MOV to operate under worst case
differential pressure
and flow conditions was not considered adequate
at this time.
The reason given was the unknown relationship between
the performance of an MOV under static conditions and under design
conditions.
The'licensee
will be
expected
to provide
a technical
justification for whatever method
is used for periodic verification of
MOVs capabilities.
Additional NRC inspection of this area
will be
required in order to evaluate the verification method used [Concern (3)].
The licensee's GL 89-10 MOV Program has established requirements for
. post-maintenance
tests to be performed on MOVs following any type of
maintenance
on the'perator or valve. These requirements are specified
in Section 9.0 of upper-tier program document Q9-MO-001
and are
implemented via site level procedure number PLP-400, Post Maintenance
Testing, and CM-P0001, Post Maintenance Testing Requirements for
Limitorque Operated
Valves.
Post maintenance
test requirements for
MOVs have
been
established
and
provisions
have- been
made
for
incorporating
baseline
tested
MOVs into the
program.
The
inspectors verified by review of objective evidence that selected MOVs,
that were baseline tested during RFO3, have been included in the PM
with a frequency for implementing PM activities that is consistent with
program
requirements.
Additionally, lubrication requirements
were
verified to have been established; and site level procedures developed for
implementing
these
requirements,
in
accordance
with
specified
11
frequencies
based
on plant operating
experience.
MOV program
procedures
do not require that "as found" periodic test be performed
prior to conducting any MOV PM's.
This is necessary
in order to
properly evaluate
existing MOV conditions, trends
and degradation
[Concer'n (4)].
The Licensee's
MOV Program
does
not address
thermal
overloads
(TOLs).
The Licensee's
commitment to Regulatory Guide 1.106 is contained
in FSAR Section 7.3.1.5.1a
Amendment No. 40.
are bypassed
under,DBA conditions.
Technical Specification Section 3.8.4.2, Motor Operated Valve Thermal
Overload Protection, specifies the surveillance required to demonstrate
operability.. Discussions with licensee's engineering personnel revealed
that TOLs ar'e sized in accordance
with guidance of IEEE 741-1990.
Surveillance requirements
are satisfied on an 18 month frequency by
implementing procedure OST-1074, Operations Surveillance Test MOV
TOL and Torque Switch Bypass Test.
No deficiencies were identified in
this area.
MOV Failures, Corrective Actions, and Trending
Recommended
action
h of the generic letter requests
that licensees
analyze
and justify each
MOV failure and corrective
action.
The
documentation should include the results and history of each as-found
deteriorated condition, malfunction, test, inspection, analysis, repair, or
alteration.
All documentation
should
be
retained
and
reported
in
accordance
with plant requirements.
It is also suggested
that the
material be periodically examined (every 2 years or after each refueling
outage after program implementation)
as part of the monitoring and
feedback effort to establish trends of MOV operability.
These trends
could provide the basis for a licensee revision of the testing frequency
established to verify periodically adequate
MOV capability. The generic
letter indicates that a well-structured and component-oriented system is
necessary to track, capture, and share equipment history data.
The inspectors reviewed the licensee's activities related to MOVfailures,
corrective actions, and trending.
The program requirements for these
elements
are. contained
in Technical
Support Management
Manual,
TMM-406, Analysis and Trending of MOV Performance.
MOV failures
are processed through the site normal work control system using Work
Requests
and Authorizations (WRSA's) and Adverse Condition Reports
(ACR's) as required to correct a problem.
MOV coordinators
are on
distribution for all WRRA as ACR's issued each day and the coordinators
track the open items on a computer data base for each MOV in the
12
program.
In addition, completed maintenance
packages
are reviewed
and kept on file by the coordinators to ensure the appropriate steps were
taken to correct the problem and to determine if the problem is isolated
or generic.
The inspectors
reviewed several files for MOV's in the
program and consider them to be an accurate,
up-to-date, machinery
history record for each valve. Since this facilityis relatively new and has
not encountered
many MOV failures, the records were readily available
for inclusion in'the machinery history records.
The
licensee's
program
requires
that
all WR&A be
reviewed
by
Engineering Support prior to work performance to ensure the proper post
maintenance
test record (PMTR) is identified and the correct planning
and procedures are specified.
In addition, the completed work package's
are
reviewed
by this
group to
ensure
the
correct root cause
is
documented, proper corrective actions were taken, and the proper PMTR
was performed.
Currently, the licensee
only trends MOV failures, however,
as more
diagnostic data becomes available additional parameters willbe trended.
TMM-406, Section 5.2, requires that MOV performance
be trended by
retention of t'est results from VOTES testing. Trends to be evaluated will
include, but not be limited to; increased or decreased
thrust values to
open or close a valve, increased or decrease motor current values.
The
inspectors reviewed the final annual MOVTrend Report dated March 23,
1992.
This report contains the failure history of the 177 valves in the
program from September
16,'1987, to date.
The inspectors considered
this report to be. very informative and will be a good basis for trending
and identification of geheric MOV failures.
The inspectors concluded that the licensee's current program for MOV
failures,
corrective action, and trending, in conjunction with planned
developments willprovide the necessary framework to monitor, identify,
and correct any adverse MOV performance.
Schedule
In GL 89-10, the staff requested that licensees complete all design-basis
reviews, analyses, verifications, tests, and inspections that were initiated
in order to satisfy the generic letter recommendations by June 28, 1994,
or 3 refueling outages after December 28, 1989, whichever is later.
The inspectors held discussions
with licensee personnel and reviewed
scheduled
MOV program activities to support
a completion date of
June 28,
1994.
The
Harris
MOV program
document
(PLP-112,
13
Revision
1 dated March 10, 1992) currently identified 116 MOVs to be
in the program. =Design basis reviews and torque/thrust calculations have
been completed for 55 MOVs. An additional'30 MOVs are scheduled to
have these activities completed by July 1992.
Baseline test and in situ
DP-flow test have been performed for.42 MOVs (refueling outage
3,
Spring 1991).
An additional 43 MOVs will be tested during refueling
outage 4 (Fall 1992) with the remaining MOVs being tested
during
refueling outage
5 (Spring 1994)
~
The inspectors concluded that the
licensee's current schedule commitments are achievable.
Overall Administration of MOV Activities
The Licensee's lower-tier program document, procedure PLP-112, Motor
Operated Valve Program, Revision 1, described the overall administrative
control of the GL 89-10 program.
Responsibility for coordinating the
implementation of the program has
been vested
with the Technical
Support Manager. Additionally, a dedicated staff of two engineers from
Technical Support-Engineering Support Section has been assigned to the
MOVprogram. Discussions with plant personnel revealed that they were
very knowledgeable of the issues involved in GL 89-10and were actively
addressing the issues toward an acceptable solution.
Based on review
of the MOVTask Force Meeting Minutes, the inspectors concluded that
the Licensee
had developed
a strong interface with industry groups.
Licensee
personnel
actively
participate
in industry
activities
in
a
leadership role.
Additionally, discussions with site personnel revealed.
that they were also involved with industry programs to keep current with
MOV activities
and
MOV diagnostic
equipment
technology.
The
inspectors
considered
these
aspects
of the licensee
program to be a
strength.
The overall administrative controls described
in site level procedure
PLP-112,
Program,
Revision 1,
was
considered
adequate.
Responsibilities have been assigned;
program requirements
have been
established; and lower-tier site level procedures have been developed to
ensure
performance
of
design
basis
reviews;
control
of
plant
modifications; control of maintenance activities; and control of analysis
and tending of MOVTest data.
Based on review of procedure PLP-112,
Paragraph 5.3
the
inspectors
determined
that
program
control
requirements
for performing periodic MOV tests
in accordance
with
approved site level procedure PM-I0043 have not been incorporated in
the
program description.
This issue
was discussed
with Licensee
personnel
and will be identified as
a concern to be evaluated
during
future NRC inspections.
MOV Setpoint Control
The inspectors found'that the licensee controls torque switch'settings
and
settings
using
Nuclear
Engineering
Department
Guidelines E-51, Revision 0 dated November 15, 1991, Control of Safety
Related
MOV Switch Settings.
The information provided
by this
procedure
is available on the licensee's
Equipment Data Base System
(EDBS), Function 480 screen.
The values determined for thrust, 'torque
and limitswitch settings for each MOV in the program are maintained at
the plant.
The ranges established for torque and limit switch settings
can not be changed without the review and approval of the Nuclear
Engineering -Department.
Training
The inspectors reviewed the licensee's MOVtraining program, courses,
facilities, and held discussions with training personnel.
The training is
conducted by the Harris Energy and Environmental Center (ELEC) which
.conducts
MOV training for all three CP5L sites.
The E5EC utilizes a
mobile training classroom
equipped
with MOVs and diagnostic test
equipment which is taken to each specific site for hands-on-training.
The inspectors reviewed the training requirements and training material
for personnel
performing MOV maintenance
and diagnostic testing.
MOV maintenance
personnel are required to complete a 40 hour4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> course
titled:
Motorized Valve Operators
- MN037G.
Personnel
performing
diagnostic testing are required to complete an additional 40 hour4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> course
titled: Valve Operator Test and Evaluation System (VOTES) MN6C01G.
The inspectors
reviewed the outlines, lesson plans, and tests for the
MOV course.
Included in the formal classroom material are discussions
of MOV 'related industry problems contained
in SOERs,
SERs,
NRC
Bulletins, Notices, and LERs.
In addition to the personnel performing
MOV maintenance
and testing, the licensee has included electrical and
mechanical
planners,
Nuclear
Engineer
Department
engineers,
and
Technical Support Group engineers in the MOV training program.
The
MOVcoordinators and various Technical Support Group personnel, have
received vendor training from BSW on the VOTES system for'diagnostic
testing.
The
inspector
reviewed
the
training records
fo'r several
maintenance/engineering
personnel associated
with the MOV program
and
found them to -be
accurate
and
adequate.
Additionally, the
inspectors reviewed the MOV awareness
training for both licensed and
non-licensed operators and found the program,to be excellent.
15
In
summary,
the
inspectors
determined
that
the
licensee
has
a
comprehensive training program and methodology to ensure that all MOV
maintenance and diagnostic analysis is performed by qualified personnel.
k.
Industry Experience and Vendor Information
The licensee's
program for reviewing industry experience
is controlled
under
Administrative
Procedure,
AP-031,
Operating
Experience
Feedback.
This procedure
provides
guidance
on the
review
and
processing of operating experience feedback information received at the
plant, and prescribes the mechanisms to ensure that any recommended
action items are identified and tracked until resolved.
This procedure
requires the Regulatory Compliance staff to screen the following OEF
items for applicability to this site and/or feedback to other CPS.L sites:
Significant Adverse Condition Reports; Documents
routed from other
company
Regulatory
Compliance
Units
which
are
designated
as
potentially warranting
OEF;
INPO Significant Operating
Experience
Reports;
Significant
Event
Reports,
Significant-by-others
Reports,
Significant
Event
Notifications,
and
Operations
and
Maintenance
Reminders;
NRC information Notices; Nuclear Network Items deemed
appropriate; and other sources deemed appropriate for OEF (e.g., Nuclear
Safety Analysis Center Reports, NRC Office for Analysis and Evaluation
of Operational Data information, etc.).
The control of 10 CFR Part 21
is under Administrative Procedure,
AP-616, Evaluating and Reporting of Defects'nd
Noncompliance
in
Accordance
with
~
Administrative
Procedure,
AP-610,
Processing
Vendor Manuals and Vendor Information, establishes
the
requirements to control the receipt,-review, approval, distribution, and
revision of vendor technical manuals
and vendor training information.
Issues
in the above categories
are tracked both manually and on
a
computer data base to ensure the required actions are complete.
The
inspectors reviewed the current indices for OEF and 10 CFR 21 items
and selected the following for further review:
90-003, Limitorque-Motor Pinion Keyway (10 CFR 21)
90-010,
Limitorque-SMB 00 Torque
Switch
Roll
Pin
Failure
(10 CFR 21).89-015, Limitorque-Cam Type Torque Switches (10 CFR 21).89-001, Limitorque-Melamine Torque Switch (10 CFR 21).
16
89-005, Limitorque - Defective Torque Switch Assembly (10 CFR 21).87-176, Limitorque Motor Operated Failure Caused by Excessive
Grease in,Spring Pack (INPO SER 20-87).87-261, Valve Inoperability Due to Unbalanced Limitorque Torque
I
86-209, Inaccurate Closed Position Indication on Motor Operated
0
84-173, Loosening of Locking Nut on Limitorque Operator (NRC
IN 84-36, Supplement
1) ~
'I
86-217,
Recent
Identified
Problems
with Limitorque
Motor
Operators
(NRC IN 86-71)
~
88-066,
Spring
Compensator
Housing
on
Valve
Operators (Westinghouse NDIS-TB-88-01).91-297,
Preliminary
Results
of Validation Testing
of MOV
Diagnostic Equipment (NRC IN 91-61).91-303,, Motor Operated
Valve Drift Due to Valve Actuator
Misadjustment (INPO ORMR 391).92-042,
Switch
Improperly Set
(ACR 91-316
from
Robinson Plant).
These
issues
were found to meet the requirements of the licensee's
programs and were included in appropriate procedures
or were in the
review process to determine corrective actions, as required.
In addition,
the
inspectors
determined
controls
were
in effect to
ensure
the
events/issues
were incorporated into licensee training materials.
In summary, the inspectors consider the licensee programs that'are in
place for ensuring
industry experience
and vendor information are
incorporated into appropriate training programs are very effective.
h
Use of Diagnostics
17
SHNPP was using the Votes diagnostic system for measuring thrust
during MOV initial set up and to monitor MOV thrust delivered during
insitu testing. Licensee personnel converted thrust values from the MOV
sizing and thrust calculations into torque values.
These torque values
were then used to set up the torque switch trip setpoint.
This was
accomplished
by using
a torque wrench which would compress
the
spring pack until a given torque was reached.
Once this torque was
accomplished the torque switch trip setpoint was adjusted to achieve
this value.
SHNPP
then
performed
a static test
using the Votes
diagnostic equipment to monitor the thrust developed.
This thrust value
's
monitored by the use of a strain gauge which is mounted on the yoke
of the valve. This strain gauge is calibrated using the Votes diagnostic
equipment.
The thrust value developed
had to be in between
the
minimum and maximum values of thrust as specified by the licensee's
calculations.
If the thrust required adjustment, the licensee would use
the torque wrench to adjust the torque switch trip setpoint and repeat
the static thrust test to ensure the adjustment fell within the required
thrust band.
The inspectors inquired as to how the licensee intended to
measure torque during insitu design basis testing.
Licensee engin'eers
stated that the torque setting based on spring pack displacement, should
not vary during static verses
dynamic testing.
The inspectors
were
concerned that without measuring torque during dynamic insitu testing,
the licensee could not detect "peak torque" which could result from
continued motor operation.
The continued motor operation would occur
due to the lag time between torque switch trip and the deenergization of
the motor control circuit.
Further, the stem coefficient of friction is
generally'higher. just at flow closure
(when the valve disc initially
contacts the valve seat) than at torque switch trip. The torque at flow
closure may differ from the torque at torque switch trip. Since the value
of torque at flow closure is used to. back calculate a stem coefficient of
friction, SHNPP may be introducing an error into their verification of the
stem coefficient of friction and masking their ability to observe
the'ffects
of ROL.
Also, the back calculated stem coefficient of friction
could change the available margin between the calculation upper thrust
window limit and the torque switch trip 'setpoint.-
This analysis
is
necessary
to verify the assumptions
used when performing the MOV
calculations.
However, licensee maintenance
personnel were involved
in purchasing
a device to measure
spring pack displacement
during
in situ design basis testing.
The inspectors will review how Shearon
Harris uses the device to measure spring pack displacement during in situ
design basis testing and how the data obtained from it is used during a
future inspection.
18
The inspectors noticed that SHNPP intended to permanently mount the
Votes strain gauges on their valve yokes. Also, SHNPP had used current
transformers to hook up their diagnostic equipment and these were left
permanently
installed.
This enabled
licensee
personnel
to hook up
diagnostic equipment easily and quickly, thereby reducing radiation dose
received to those involved in the testing.
This also enabled the licensee
to hook diagnostic equipment for retesting if any maintenance
had been
performed with'ease and a minimal amount of set-up time required. The
inspectors considered this to be a strength.
4.
Exit Interview
The inspection scope and all findings were summarized on April 10, 1992, with
those persons indicated in the Appendix 1.
The licensee was apprised of the
concerns identified during the inspection and listed in the "SUMMARY"at the
beginning of this report..
19
APPENDIX
PERSONS CONTACTED .
Licensee Employees
"E. Burkhead, Senior Instructor, Nuclear Training
"M. Grantham, Senior Engineer, Nuclear Engineering Department
"D. Hawley, Senior Engineer, Nuclear Assessment
Department
"T. Helms, Project Engineer, Nuclear Engineering Department
"P. Hicks, Electrical Engineer, Nuclear Engineering Department
C.,Hinnant, General Manager, Harris Plant
"D. Kanning, Senior Engineering Technical Support
"S. Mabe, Project Engineer, Nuclear Assessment
Department
"M. McDaniel, Mechanical Engineer, Nuclear Engineering Department
"J. Nevill, Manager, Technical Support
"C. Olexik, Manager, Regulatory Compliance
"M. Pugh, Project Engineer, Nuclear Engineer Department
"M. Verrilli, Senior Specialist, Regulatory Compliance
"L. Woods, Manager, System Engineering-
"G. Young, Engineer, Technical Support
"R. Zula, Manager, Engineering/Technical Support
NRC Personnel
"J: Tedrow, Senior Resident Inspector"
"M. Shannon,
Resident Inspector
"Attended Exit Interview
e