ML18058A394
| ML18058A394 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 04/29/1992 |
| From: | Ring M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Slade G CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| Shared Package | |
| ML18058A397 | List: |
| References | |
| GL-89-10, NUDOCS 9205050082 | |
| Download: ML18058A394 (14) | |
See also: IR 05000255/1992014
Text
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APR 2 9 l99l
' *
Docket No. 50-255
'-= Consumers Power company
ATTN:
Mr. Gerald B. Slade
General Plant Manager
Palisades Nuclear Plant
27780 Blue Star Memorial Highway
Covert, MI
49043
Dear Mr. Slade:
This letter refers to the routine safety i'nspection conducted by
Messrs. G. D. Replogle and J. F. Smith, and Miss C. A. Gainty of
this office on March 24 through April 3, 1992.
The inspection
included a review of activities authorized for your Palisades
Nuclear Generating Plant.
At the conclusion of the inspection,
the findings were discussed with those members of your staff
identified in the enclosed report.
The areas examined during the inspection are identified in the
report.
These areas consisted primarily of a review of the
Palisades Motor Operated Valve Program established in response to
Within this area, the inspection consisted
of a selective examination of procedures and representative
records, observations, and interviews with your personnel.
No violations of NRC requirements were identified during th~
course of this inspection.
In accordance with 10 CFR 2.790 of the Commission's regulations,
a copy of this letter, and the enclosed inspection report will be
placed in the Public Document Room.
We will gladly discuss any questions you have concerning this
inspection.
Enclosure:
Inspection
Report-Ne~-50-255/92014(DRS)
See Attached Distribution
. ll-
RIII
~
~'iig e/jk
04/28/92
9~05050082 920429
POR
ADOCK "05000255
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Sincerely,
M. A. Ring, Chief
Engineering Branch
' *-- Consumers Power Company
Distribution
cc w/enclosure:
David P. Hoffman, Vice President
Nuclear Operations
P. M. Donnelly, Safety
and Licensing Director
DCD/DCB (RIDS)
OC/LFDCB
Resident Inspector, RIII
James R. Padgett, Michigan
Public Service Commission
Michigan Department of
Public Health
Palisades LPM, NRR
SRI, Big Rock Point
w. Hodges, RI
A. Gibson, RII
s. Collins, RIV
R. Zimmerman, RV
T. Scarbrough, NRR
2
APR 2 9 1992
J
.:....
' **
U. S. NUCLEAR REGULATORY COMMISSION
REGION III
Report No.: 50-255/92014(DRS)
Docket No.: 50-255
License No.: DPR-20
Licensee:
Consumers Power Company
212 West Michigan Avenue
Jackson, MI
49201
Facility Name:
Palisades Nuclear Generating Plant
Inspection At:
Palisades Site, Covert, MI
through April 3, 1992
Approved
obson, Chief
s & Processes Section
Inspection Summary
t(-2 Y-~ z..._
Date
l./- -:i.y- f 1....
Date
Inspection conducted March 24 through April 3, 1992 (Report No.
50-255/92014(DRS))
Areas Inspected:
Announced safety inspection of the licensee's
response to Generic Letter (GL) 89-10, "Safety-Related Motor-
Operated Valve (MOV) Testing and Surveillance" (2515/109) and
licensee actions on previously identified items of noncompliance
(92701) .
Results:
No violations or deviations were identified.
One open
item was disclosed (Paragraph 3.a. (2) (b)).
The licensee demonstrated strengths in the following areas:
0
The technical knowledge and expertise of the MOV coordinator
was exceptional.
0
Steps taken to address inaccurate actuator information
supplied by the vendor weie excellent.
9205050088 920429
ADOCK 05000255
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I
Inspection Summary
2
0
The scope and intent of the self-assessment addressing the
recommendations of GL 89-10 were excellent, although
followup actions were deficient.
The licensee demonstrated weaknesses in the following areas:
0
0
0
The program implementation had not shown significant
progress for the past two years.
Evaluation of test data had not started at the time of the
inspection.
Analysis and calculations addressing degraded voltage,
design basis requirements, thrust requirements, and thermal
overload sizing were not complete at the time of the
inspection and may adversely impact the schedule for
completion of the program .
1.
2 .
3.
TABLE OF CONTENTS
Persons Contacted ......................*.**... ~********
1
Licensee. Action on Previous Inspection Findings .....***
1
Inspection of the Palisades Program Developed in
Response to Generic Letter 89-10 ..........*.**......*
1
a.
Generic Letter 89-10 Program Review .....*.***.**.*
1
(1) Scope of the Generic Letter Program .**...**...
2
(2) Design Basis Reviews .....*.***.*......***..***
2
(3) MOV switch Settings .........******..*..**.....
4
(4) Design Basis Differential Pressure and Flow
Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
(5) Periodic Verification of MOV Capability ***.*..
5
(6) MOV Failures, Corrective Actions and
Trending. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
( 7) Schedule. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
b.
Associated Programmatic Reviews .*.******..*..****.
6
(1) Design Control for Thermal overload
Protect ion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
(2) MOV Setpoint Control .............*.*......***.
6
( 3) *Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7
( 4) Training. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8
(5) OJ?eratin<! Experience and Ven,dor Notification..
8
(6) D1agnost1cs............................ ... . . . . .
8
4.
Licensee Self-Assessment~ ............*..*.*.**....*..**
9
5.
Open Items . ................ * .... * ............. *. . . . . . . . . . .
9
6.
Exit Meeting ... ~.......................................
9
i
DETAILS
1.
Persons Contacted
Consumers Power Company (CPCo)
- T. Palmisano, Administrative and Planning Manager
- G. Brock, Electrical Engineer
- P. Donnelly, Director, Plant Safety and Licensing
- B. Gerling, Safety Analysis Supervisor
- J. Kuemin, Licensing Administrator
K. Osborne, Systems Engineer Manager
- P. Rigozzi, Training Administrator
- G. Smith, Systems Engineer
- B. Vanwagner, Systems Engineer
- E. Zernick, Performance Assessment
U. S. Nuclear Regulatory Commission CNRC)
J. Heller, Senior Resident Inspector
- R. Roton, Resident Inspector
- Denotes those attending the exit meeting on April 3, 1992.
2.
Licensee Action on Previous Inspection Findings (92701)
(Closed) Violation 50-255/89007-0JCDRS):
Low temperature
overpressurization setpoints for M0-27B and M0-27C in the
primary coolant system exceeded the technical specification
allowable value on several occasions.
The inspector's
review of the corrective action confirmed that the necessary
technical specification change had b~en processed to
preclude a recurrence of the problem.
This violation is
closed.
3.
Inspection of the Program Developed in Response to Generic
Letter 89-10
a.
Generic Letter (GL) 89-10 Program Review
The NRC inspectors reviewed the commitments contained
in the licensee's response submitted to the NRC by
letter dated December 20, 1989.
No exceptions were
taken to the recommendations outlined in the GL.
The NRC inspectors reviewed procedure EM-28-01, "Motor
Operated Valve Program" Rev. o, dated December 19,
1990.
The document did not reflect the actual program.
being implemented at the time of the inspection.
For
example, the licensee planned to revise all of the
"Design Basis DP Documents."
However, the program
1
document referenced only the old dp documents and made
no mention of the revisions.
Another example was that
the program document specified preventive maintenance
frequencies of two and four years depending on the type
of maintenance performed, while the aqtual frequencies
were every two and four refueling outages,
respectively.
Revisions to the program document should
be made so that the document accurately reflects the
program being implemented.
The program implementation had not shown significant
progress for the past two years.
The inspectors
considered the lack of progress for such a sustained
period of time to be a weakness.
(1)
Scope of the Generic Letter Program
The Palisades plant had a total of 62 MOVs.
Sixteen were in the circulating water system and
were not safety-related.
The inspectors reviewed
the engineered safety, chemical volume and
control, and auxiliary feedwater systems as a
sample check for the completeness of the scope of
the GL 89-10 program.
No problems were found.
The NRC inspectors reviewed written justification
for the exclusion of 12 MOVs from differential
pressure (dp) testing and found it to be within
the guidelines of the GL with one exception.
block valves M0-1042A and M0-1043A were grouped
based on dp testing performed on M0-1042A and an
extensive dimensional analysis of the two MOVs.
The licensee claimed that because tpe MOVs
appeared to be identical, testing of M0-1043A was
not necessary.
However, industry test data has
shown that apparently identical MOVs often do not
perform in an identical manner when subjected to
design basis testing.
Valve M0-1043A should be
tested if practicable or justified for exclusion
from dp testing in accordance with the
recommendations outlined in. the GL.
The inspectors determined that the scope of the
program was consistent with the guidance of GL 89-
10, with the exception of valve grouping.
(2)
Design Basis Reviews
(a)
Differential Pressure Requirements
Work had not started on updated design basis
documents (DBDs) to address maximum operating
2
conditions.
However, the NRC inspectors
found the methodology for revising the DBDs
to be conservative.
(b)
Reduced Voltage Capability
Procedure number EM-28-0l, "Motor Operated
Valve Program," Rev. O stated that degraded
voltage was not considered in the design
basis calculations because the voltage at the
motor terminals was assumed to be greater
than 90%, which was consistent with the
Limitorque recommendations.
However, no
engineering analysis was performed to support
this assumption.
surveillance Report S-QC-
89-07, dated March 9, 1990 identified this to
be a deficiency.
Corr.ective actions were not
taken at that time, but funding for future
analysis was requested prior to this NRC
inspection.
The NRC inspectors and the licensee performed
separate degraded voltage calculations for a
sample of six MOVs to determine actual worst
case motor terminal voltages.
The results
from the two analysis methods agreed within
acceptable margins.
Four of the calculations
showed the degraded voltage values available
at the motor terminals to be less than 90% of
the nominal 460V rating.
The worst case
voltage available for M0-3008 was only 60% of
the nominal voltage.
The licensee committed
to perform detailed degraded voltage analysis
for all MOVs in the GL 89-10 program at
Palisades.
The NRC inspectors found, through
calculations, that MOVs M0-0501 and M0-0510
(MSIV bypass valves) may not develop enough
thrust under degraded voltage conditions to
close during a design basis event (steam line
break).
Furthermore, during static testing
the MOVs appeared to have unusually high stem
factors, which may indicate degradation of
the stems and/or stem nuts.
An analysis was
performed to show that the position of the
MOVs would be insignificant during the
postulated event, however, the portion of the
analysis addressing the event at the end of
core life (ECL) was not expected to be
finished until September 30, 1992 (prior to
ECL).
This will be considered an open item
3
- "'
(c)
pending further NRC review of the completed
analysis. (50-255/92014-0l(DRS))
The program did not-consider the effects of
high ambient temperatures on the performance
of MOV motors.
However, Limitorque was
performing testing and analysis to address
this issue.
Information from the testing
should be incorporated into the program when
it becomes available.
Completed Design Basis Review
Revised DBDs were not complete at the time of
the inspection.
However, old DBDs were
available for reference which were prepared
in response to NRC Bulletin (IEB) 85-03.
The
NRC inspectors reviewed several of the old
design basis documents and found them to be.
conservative, although lacking in detail.
In
general, the old DBDs did not address valve
mispositioning.
The licensee planned to
incorporate mispositioning into the new DBDs
if the results of the mispositioning appeal,
currently being reviewed by the NRC staff,
dictates.
(3)
MOV Switch Settings
Actuator thrust calculations (used to set torque
switches) were not complete at the time of the
inspection but were scheduled to be finished by
the end of 1992.
The methods for calculating thrust included
provisions for adding a 30\\ margin to the*
calculated minimum required thrust to account for
diagnostic equipment inaccuracies, torque switch
repeatability,- and MOV degradation.
The
inspectors indicated that the 30% margin may not
be enough to envelop large inaccuracies that may
be experienced by the Motor Operated Valve
Analysis and Test System (MOVATS) that was used
during testing.
Steps should be taken to ensure
that margins used are adequate.
The licensee planned to use valve f.actors of 0.4
for flex-wedge gate valves, 0.2 for parallel disc
gate valves, and 1.1 for globe valves.
A
coefficient of friction for the stem/stem nut
interface of 0.2 was assumed.
These factors are
considered to be acceptable provided the
4
evaluation of test data shows them to be
conservative.
Rate-of-loading was not addressed in the program,
although an effeGt from rate-of-loading was
apparent in the test data.
Additional margin
should be added to calculations to envelop this
effect, when applicable.
(4)
Design Basis Differential Pressure and Flow
Testing
The NRC inspectors reviewed the methods for dp
testing several MOVs and found them to be
conservative.
(5)
Periodic Verification of MOV Capability
The plan for periodic verification of MOV
capability included static diagnostic testing of
MOVs every fourth refueling outage.
The period
recommended by the GL was every third refueling
outage.
The licensee committed to change the
period to conform with the recommendations of the
GL.
The NRC inspectors informed the licensee that
static testing was not currently an acceptable
method of periodic verification because of
uncertainties in the performance of MOVs under
static and design basis conditions.
In some cases, baseline static testing was
performed on MOVs prior to maintenance (a degraded
condition), while dp testing was performed after
maintenance.
The condition of the MOV during a
static baseline test should be the same as it was
when the MOV was dp tested.
Comparing test
results after maintenance to baseline test data
taken before maintenance makes detection of MOV
degradation unlikely.
Steps should be taken to
ensure that the data taken during baseline testing
is meaningful.
Most of the MOVs tested under differential
pressure conditions were tested in response to IEB
85-03.
Although the testing satisfied the
recommendations of GL 89-10, some MOVs were tested
as early as 1987.
These MOVs may require re-
testing in 1992 to meet the schedule for periodic
verification.
5
(6)
(7)
MOV Failures, Corrective Actions and Trending
MOV failures were reviewed and found to be
properly analyzed and documented.
The corrective
actions were specified and scheduled to ensure
completion.
The licensee did not have a program in place to
evaluate test data.
A program, with definitive
acceptance criteria, should be developed to
evaluate valve and stem factors experienced during
design basis and static testing.
The lack of an
evaluation program is considered to be a weakness.
Schedule
Fourteen MOVs that still re'quire dp testing were
scheduled to be tested within a time frame
consistent with the GL.
However, at the time of
the inspection, the revised DBDs, thrust
calculations, degraded voltages calculations and
.thermal overload (TOL) sizing calculations were
not started.
The results of the revised DBDs and
calculations may require torque switch setting
adjustments and/or TOL replacements for a large
number of MOVs.
Because of this, completion of
all the work necessary to close out the.GL, within
the schedule, may be improbable.
The lack of
updated design basis analysis and calculations
were considered to be a weakness.
b.
Associated Programmatic Reviews
(1)
Design Control for Thermal Overload Protection
The NRC inspectors reviewed documents that
addressed the methods for the design control of
TOLs.
At the time of the inspection, TOLs were
bypassed except for indication purposes.
However,
the program document noted plans to use TOLs in
MOV circuits in the future and to size TOLs based
on guidance from IEEE 741-1990.
Based on the
intentions specified in the program document,
design control for TOL protection appeared to be
acceptable.
(2)
MOV Setpoint Control
The methods for ensuring integrity of setpoint
calculations and setpoint control were reviewed.
Both the calculation of the settings and the
setting of the MOV switches are prescribed in
6
formal procedures which require authorization by
cognizant personnel to institute changes.
The
record of switch settings is maintained in a
controlled document which cannot be changed
without proper authorization.
The MOV setpoint
control program appeared to be protected from
unauthorized modification.
(3)
Maintenance
Several minor deficiencies were noted during plant
walkdowns.
Three MOVs were leaking oil from the
actuators, two MOVs were oriented such that the
spring pack was located below the actuator (which
could make hydraulic lock of the spring packs more
likely), and one valve stem appeared to be without
lubrication.
The licensee agreed to evaluate the
deficiencies and take appropriate corrective
actions where warranted~
The nominal stem lubrication frequency (every two
refueling outages) was longer than the 18 month
frequency recommended by Limitorque.
Furthermore,
the frequency was not consistent with the program
document which specified the lubrication of MOV
stems every 24 months.
The licensee agreed to
change the frequency of stem lubrication to an
i~terval not to exceed the Limitorqua
recommendations.
The lubrication frequency may be
increased in the future if information from
various industry testing programs indicates that
an extended frequency is warranted.
Testing was not performed after packing
adjustments unless the originally specified
packing gland torque w~s exceeded.
Test data was
presented which showed that the stem load due to
packing increased only slightly after adjustment.
However, the test data was limited in that testing
was only performed on one MOV and neglected the
effects of various foreign materials (such as
boric acid crystals that may be present at the
stem/packing interface) or packing damage (that
may occur as a result of a packing leak).
The
justification for not testing after minor packing
adjustments was found unacceptable because of the
lack of sufficient test da~a.
The licensee will
be expected to develop better justification to
support its position or develop plans to test MOVs
after *minor packing adjustments.
Adequate
justification may include an engineering
evaluation after adjustments to ensure that
7
substantial margin is available in the event that
packing loads are greater t'han anticipated.
Periodic refurbishment of actuators was not
performed.
Instead, refurbishment requirements
were based solely on trending results from
diagnostic test data.
Since some forms of
degradation are not detectable (in diagnostic
data) until the valve is rendered inoperable,
trending alone may not be sufficient.
A
supplemental periodic visual inspection of a
sample of MOVs would strengthen the existing
program.
(4)
Training
The NRC inspectors reviewed course outlines,
technical texts, training facilities, training
records, examinations, and descriptions of on-the-
job training provided to. personnel performing work
associated with the Palisades MOV program.
The
MOV training program at Palisades was considered
acceptable.
(5)
Operating Experience and* Vendor Notification
The NRC inspectors reviewed applicable procedures
and discussed the process for handling various
information notices from different so~rces.
The
licensee had taken steps to ensure that
information received was screened, evaluated and
maintained by appropriate organizations and that
appropriate actions were planned.
The* Palisades
program for the processing and control of
operating experience and vendor notifications
appeared to be acceptable.
Some Limitorque nameplates, and other information
documents issued by Limitorque, are known to have
inaccurate information.
However, steps had been
taken to ensure that the information used from
these sources was accurate.
These steps included
a visual examination of actuator parts during
refurbishment and a review of motor current
traces.
Palisades' extensive effort to address
this issue was considered t.o be a strength.
(6)
Diagnostics
Palisades currently uses VOTES diagnostic
equipment to test MOVs under both static and
dynamic conditions.
However, most of the
8
diagnostic testing previously performed used
MOVATS diagnostic equipment.
MOVATS equipment has
come under scrutiny with regard to its published
inaccuracies.
Since all of the design basis
diagnostic testing was performed at or near full
flow/dp conditions, the effects of the
inaccuracies may be insignificant.
However, if
degraded voltage concerns arise, the data from
MOVATS testing may be necessary to show
operability.
In these inst.ances, appropriate
values ~or diagnostic equipment inaccuracies
should be used.
Most static baseline diagnostic tests (performed
in the same general time frame as the design basis
dp tests) specified MOVATS diagnostic equipment
for data collection.
Subsequent static testing
specified the use of VOTES equipment.
Steps
should be taken to ensure that the comparison of
data from the two different diagnostic equipment
systems is meaningful.
4.
Licensee Self-Assessment
The self-assessment in the area of MOVs was evaluated by
review of Surveillance Report S-QC-89-07 dated March 9,
1990.
Although other surveillance was conducted on portions
of the program, this was the only report dedicated to
evaluation of the plant's compliance with the
recommendations of GL 89-10.
The scope and intent of the
effort was excellent in that it compared the program to
specific NRC commitments.
Howe.ver, some followup corrective
actions were deficient.
For example,* corrective actions for
degraded voltage issues were inadequate.
5.
Open Items
An open item is a matter that requires further review and
evaluation by the inspector, including an item pending
specific action by the licensee.
An open item disclosed
during this inspection is discussed in Paragraph 3.a. (2) (b).
6.
Exit Meeting
The inspectors met with licensee representatives (denoted in
Paragraph 1) at the conclusion of the inspection on April 3,
1992.
The inspectors summarized the purpose and scope of
the inspection and the findings.
The inspectors also
discussed the likely informational content of the inspection
report with regard to documents or processes reviewed by the
inspectors during the inspection.
The licensee did not
identify any such documents or processes as proprietary.
9