ML20237G287

Insp Rept 50-344/87-20 on 870518-21.No Noncompliance or Deviations Noted.Major Areas Inspected:Licensee Programs Re Check Valves & Licensee Response to INPO Significant Operating Event Rept 86-03.Two Open Items Identified

ML20237G287
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	07/27/1987
From:	Abbate C, Baker E, Albert Lee, Stone J Office of Nuclear Reactor Regulation
To:
Shared Package
ML20237G257	List: ML20237G254 ML20237G287
References
50-344-87-20, NUDOCS 8708130387
Download: ML20237G287 (11)

See also: IR 05000344/1987020

Text

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OFFICE OF HUCLEAR REACTOR REGULATION

Report No.: 50-344/87-20

Docket No.: 50-344

License No.: NPF-1

Licensee: Portland General Electric Company

121 S.W. Salmon Street

Portland, Oregon 87204 ,

Facility Name: Trojan Nuclear Plant

Inspection At: Rainier, Oregon

Inspection Conducted: May s18-21, 1987

Inspectors:  %" [ v W

Edward T. Baker, leam Leader ' Date l

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Pro ran Development and Reactor Inspection Section (PDRIS)

Ud fhl* Wht - *

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Claudia M. Abbate, PDRIS 6' Ddte l

W 'z- / / 5

Krnold J. H. Lee, MechanicaF Engineering Branch ' D#te  !

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Consultant: Charles Allen, NEAC

Approved By: &;_ [ ,

James C. Stone, Chief, PDR15

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Vendor Inspection Branch

Summary:

Inspection During the Period of May 18-21, 1987 - (Report No. 50-344/87-20)

Areas Inspected: This special, announced inspection was conducted to gather

information on the licensee's programs for inspecting and testing check valves,

performing preventive maintenance on check valves, the location of check

valves with respect to sources of turbulence, and the licensee's response to

the Institute for Nuclear Power Operation (INP0) Significant Operating Event

Report (SOER) 66-03 concerning check valves.

Results: No items of noncompliance or deviations were identified. Two open

items concerning check valve testing were identified, 50-344/87-20-01 and

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87-20-02. These items will be considered during the review of your inservice

testing p,rogram for the second ten year interval. The inspection did reveal

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that to date, valves located in areas of turbulent flow were not all receiving

preventive maintenance or being tested in a manner that would ensure valve disk

and sea't integrity. However, the newly established check valve reliability and

enhanced testing programs, if effectively implemented, should result in improve-

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ments in check valve performance and plant safety.

8708130307 870{'y 4

ADOCK 050

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1.- Persons Contacted

Licensee Representatives-

• D. W. Cockfield, Vice President, Nuclear

A. Cohlmeyer, Plant Maintenance

• G. J. Kent, Trojan Plant Engineer (IST)

• D. Keuter, Manager, Technical Services

• P. A. Morton, Branch Manager, Trojan Engineering

M. Malmros, Nuclear Safety and Regulation

• D. Nordstrom, Nuclear. Safety and Regulation

• C. A. Olmstead, Generator Manager

I *R. C. Rupe, Supervising Engineer

• R. Schmitt, Manager, Operations and Maintenance

• M. Schwartz, Plant Maintenance

• D. Seely, Plant Engineer

• D. W. Swan, Supervisor, Maintenance

• T. Walt, Manager, Nuclear Safety and Regulation

G. Zimmerman, Nuclear Safety and Regulation

a

USNRC

G. Suh, Resident Inspector l

• T. Chan, Project Manager

• E. Merschoff, Acting Chief, Vendor Inspection Branch

2. Scope

The licensee's programs for testing, inspecting, and performing maintenance

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on check valves were reviewed to determine the program's ability to ensure

valve disk and seat integrity. An inspection of selected valves for location

in relation to sources of turbulence (i.e., elbows, tees, pump discharge outlets)

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was performed. The licensee's response to INP0's SOER 86-3 concerning check

l valves was also reviewed.  ;

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! 3. Licensee Action and Previously Identified Problems

This subject was not addressed during this inspection.

4. Response to SOER 86-03

The licensee had developed a formal response to the SOER under their Operational

! Assessment Review (OAR) program. The response, 0AR-86-11, states that the Trojan

l System Reliability Review Program, Plant Engineering Procedure PEP-20-11, includes

the identification of check valves within systems that are essential for the-

, reliable operation of the plant. A list of check valves identified as essential

! will be provided to the IST engineer for inclusion in the IST program. Systems

listed for inclusion in the reliability review include main steam; service

water; component cooling water; main feedwater; auxiliary feedwater; emergency

diesel starting air; high head, medium head and low head safety injection;

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• Indicates those who attended the May 21, 1987 exit meeting.

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accumulator safety injection and residual heat removal. In addition to identifying

check valves to be tested, the program also includes a review cf existing test

procedures to ensure that the test can detect valve degradation or inoperability.

The reliability review program established December 31, 1987 as a target

date for identifying essential check valves and revising or developing test

procedures. Improvements in the testing of some valves has already been

proposed by plant engineering personnel and is awaiting management approval 4

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prior to implementation.

The reliability review program also discusses what actions will occur after the q

Owners Groups Task Force issues the guidelines for reviewing check valve design. '

This design review will include location, orientation, size, and type of valves.

The target date for the completion of the design review is December 31, 1988.

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Discussions with engineering and management personnel indicate that PGE is l

aggressively developing an enhanced program of '.esting, inspection, and l

maintenance which, if implemented, should substantially reduce the likelihood i

l of failed check valves going undetectea and exacerbating the consequence of a j

plant event. . .

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5. Review of Check Valves j

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Using probabilistic risk assessments from similar plants and failure data j

from licensee event reports (LERs), the inspectors selected 113 check valves ]

in 13 different systems (safety related and balance of plant) for inspection. i

The 113 check valves consisted of 30 pump discharge and 83 in-line check valves.  !

The inspectors physically examined 40 of the valves to identify their location

with regard to proximity to flow disturbances (e.g., elbows, tees, pump discharge

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outlets) and reviewed testing proceduras and maintenance records for all 113

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valves.

The review of pump discharge check valves indicated that 4 were tested in a

manner which would provide irF :ation of disk and seat integrity, 15 are i

exercised manually or by passing flow, and 11 are not covered by a documented  !

test procedure. The installed configuration was examined for 26 of these

valves and all the valves were located in close proximity to sources of

turbulence. Maintenance records for the period 1980 to May 1987 indicated that

19 valves had received no maintenance, 11 valves had received corrective

maintenance and that 3 of the valves that received corrective maintenance were

currently receiving preventive maintenance.

The review of in-line check valves indicated that 42 valves are leak tested,

11 are tested by other means which provide an indication of disk and seat

integrity, 19 are exercised manually or by passing flow and 11 ere not covered

by a dccumented test procedure. The installed configuration was examined for 14

valves and all were located in close proximity to sources of turbulence.

Maintenance records for the period 1980 to May 1987 indicated that 65 valves had

not received any maintenance, 18 valves had received corrective maintenance and

l 8 of the valves that received corrective maintenance were currently receiving

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preventive maintenance. It should be noted that for the purposes of this

summary, maintenance to correct minor external leakage past gaskets and packing

was classified as not receiving maintenance because it does not affect disk

and seat ' integrity.

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A description of the results of this review for each check valve application

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follows. Only those maintenance records dealing with valve operability or

disk and seat integrity between 1980 and the present are discussed.

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5.1 Auxiliary Feedwater (AFW) Check Valves

Check valves FW-2034 and FW-2035 are located in the 2-inch recirculation i

line to the condensate storage tank and are forward flow tested under the  ;

Inservice Test (IST) program. The valves are not reverse flow or leak l

tested. A review of maintenance records indicated no maintenance relevant

to disk or seat integrity had been performed on these valves for the time

period which was reviewed. l

Check valves FW-2032 and FW-2033 are'the 6-inch auxiliary feedwater pump

discharge check valves. These valves are currently full stroke exercised l

during cold shutdown under Periodic Operability Test POT-5-3, the procedure l

for implementing the IST program. Additionally, the licensee has proposed l

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to periodically test the valves for disk and seat integrity under Periodic

Engineering Test PET-1.4rl, by pressurizing the volume of piping downstream

of the valves with air and monit,oring the air pressure decay rate. These

valves were physically examined"and were found to be attached on the inlet

side to a 90* elbow that was attached to the pump discharge and have an

isolation valve attached on the discharge side. A review of maintenance

records indicated no maintenance relevant to disk or seat integrity had

been performed on these valves during the time period reviewed.

Check valves FW-2027 and FW-2029 are located in 6-inch suction lines l

between the AFW pump inlets and the condensate storage tanks. These i

valves are exercised under the IST program. Additionally, under POT-5-1, I

the licensee measures the breakaway force required to move the disk off

its seat. This is done using a calibrated spring scale to measure force

epplied to an external manual operator as an indication of disc integrity. l

The breakaway force data are recorded and trended. These valves were l

physically examined for location. Check valve FW-2027 had a gate valve  ;

attached on the inlet side, preceded by a 90* elbow, and a tee attached I

to the outlet. Check valve FW-2029 had a 90a elbow attached to the inlet '

and a gate valve attached to the outlet, followed.by a butterfly valve.

A review of the maintenance records indicated no maintenance had been

performed on check valve FW-2027 during the time period reviewed. Check

valve FW-2029 received maintenance under Maintenance Request (MR) 86-4783

after failing to move off its seat within the acceptance criteria of

POT-5-1. The valve was cycled, lubricated, and retested with acceptable

results. ,

Check valves FW-2028 and FW-2030 are located in 6-inch suction lines ,

between the AFW pump inlets and the service water system. Under POT-5-1,

the licensee measures the breakaway force required to move the disk

off its seat using a calibrated spring scale as an inoication of

disk integrity. The breakaway force data are recorded and trended. The

valves are also manually cycled full open and closed. The valve is not

flow tested because the flow through the valve would contaminate the AFW

system with service water. Check valve FM-2028 had a 90 elbow attached

to fts inlet and a gate valve attached to its outlet. A butterfly valve

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was attached to the outlet of the gate valve. Check valve FW-2030 has a

gate valve attached to its inlet and a 90 elbow attached to its outlet.

A tee is attached to the outlet of the 90' elbow. A review of maintenance

records indicated na maintenance relevant to disk or seat integrity had

been performed on these valves during the time period reviewed.  ;

Check valves FW-2013, FW-2014, FW-2015, and FW-2016 are located in 3-

inch lines between the comon AFW supply header and main feedwater lines

A, B, C, and D, respectively. These valves are exercised during forward

flow testing under POT-5-3 during cold shutdown. The valves are not

tested in a manner that verifies disk integrity. A review of maintenance

records did not reveal any maintenance involving disk or seat integrity.

Check valves FW-2009, FW-2010, FW-201-1, and FW-2012 are located in 3-

inch lines between the diesel driven AFW pump and main feedwater lines

A, B, C, and D, respectively. Check valves FU-2005, FW-2006, FW-2007,

and FW-2008 are located in 2-inch lines between the turbine driven AFW

pump and main feedwater lines A, B, C, and D, respectively. These valves

are exercised during forward . flow testing under P0T-5-3. Additionally,

the licensee has propo' sed to periodically test the valves for disk inte-

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grity under PET-14-1 by pressurizing the volume of piping downstream

of the valves with air and monitoring the pressure decay rate. A review

of the maintenance records indicated that no maintenance relevant to disk l

or seat integrity had been performed on these check valves during the i

time period rev1ewed. -

5.2 Chemical and Volume Control System (CVCS) Check Valves

Check valves 8378B, 8379B, and 8381 are located in 3-inch lines

between the charging pumps and reactor coolant piping in the charging line,

alternate charging line, and common supply line, respectively. Aside from

obser"ing unrestricted flow during plant operations, these valves are not

incluced in any test procedure, nor is their proper operation recorded

anywhere. The licensee claimed that the valves did nat need to be tested

because they are always experiencing full flow, are always in the open

position, and therefore are not required to be exercised under the

Section XI IST requirements for check valves normally in the open position.

However, the check valve in the idle charging line is normally closed

anc would aerform an isolation function if a piping rupture occurred in

the idle c1arging line. Therefore, check valves 8378B and 8379B should

be exercised and be shown to close on cessation of flow. This lack of

testing is considered an open item (50-344/87-20-01) and will be reviewed

as part of th6 NRC's review of the licensee's submittal of the IST program

for the second 10-year interval, which is currently in progress.

Check valve 8497 is installed 2 feet downstream of the positive displace-

ment charging pump (PDP), and has an isolation valve attached to its outlet.

Because cf vibration problems, the PDP is no longer used and, therefore,

this check valve is not tested in any manner. This approach appears

acceptable because the tolerances in a PDP would limit leakage through

the pump.

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Check valves 8481A and 8481B are the centrifugal charging pump discharge

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check valves and are installed with 90* elbows attached to both the

inlets and the discharges of the valves. On the inlet side, the 90* elbows

are attached to tees that are attached to the pump discharges. On the

l outlet side, the 90" elbows are attached to tees that are attached to the

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charging header. These valves are forward flow tested under POT-9-1,

which implements the IST program. Although there is currently no reverse

flow testing, one of the recommendations of the check valve reliability

study was to monitor pump discharge pressure on the idle pump. Failure

of the valve to seat on cessation of flow or reverse flow could result in

short circuiting the charging flow and reducing flow delivered to the

reactor coolant system. This testing should be considered for inclusion

in the IST prog am for the second 10-year interval. As such, this is

considered an open item (50-344/87-20'-02) and will be reviewed as part of

the NRC's review cf PGE's program for the second 10-year interval.

A review of maintenance records indicated that no maintenance relevant to  !

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disk or seat integrity had been performed on the CVCS valves that were

reviewed. . I

5.3 Cenponent Cooling Water (CCW) Ch'eck Valves

Valves CC-2033, CC-2034, CC-2044, and CC-2045 are 1-1/2-inch spring-loaded

lift check valves located at the discharge of the CCW makeup pumps.

Although the drawings indicated two spring-loaded check valves in series  ;

at each pump discharge, physical examination indicated the spring and valve

internals had been removed from one valve at each pump. The remaining

o)erational valves are installed with a 90' elbow attached to the inlet,

w11ch is attached to the pump discharge, and the second check valve body

attached on the outlet. Currently there is no documented testing performed

on these valves. When the pumps are run, the valves are forward flow

tested but the results are not documented. If the valves fail to pass

flow, a maintenance request is generated to correct the problem. A review

of maintenance records indicated that valve CC-2044 was found stuck open

and valve CC-2045 was found stuck closed during work performed under MR

81-3485 dated August 16, 1951. The licensee intends to evaluate these

check valves as part of the check valve reliability program.

Check valves CC-2035, CC-2036, CC-z046, and CC-2047 are located in 1-1/2-

inch lines supplying cooling water to the reactor coolant pump thermal

barriers. No documented testing is performed on these normally open

check valves. A review of maintenance recorcs indicated that valve CC-2046

was found stuck closed during work performed under MR 85-3481, dated

July 9, 1985. These check valves provide the aressure isolation boundary

between the 2500-psi rated piping and thermal aarrier and the 150-psi

rated CCW system upstream of the valves. If the thermal barrier should

rupture, the pressure relief valve on the CCW system might not be able to

prevent overpressurization of the CCW system. The licensee plans to

evaluate these valves as part of the check valve reliability program.

Check valves CC-2037 and CC-2039 are 24-inch valves located at the

discharge of the CCW pumps. The valves are installed with a 90' elbow

atte.hed to the valve inlet and the elbow inlet is attached to the pump

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discharge. On the outlet side of the valve is another 90 elbow attached

to an isolation valve that has a 90 elbow attached to its outlet. A

review of the maintenance records for these valves indicated that no

maintenance relevant to disk or seat integrity had been performed during l

the time period reviewed.

Check valves GS-2001 and GS-2002 are located in the 1-inch line supplying )

nitrogen to the CCW surge tank from bulk storage. Check valves GS-2004

and CS-2003 are located in a 1/2-inch line between nitrogen supply bottles

and the CCW surge tank. The valves are exercised using forward flow during .

operations and are leak rate tested under Temporary Periodic Test TPT-197. l

A review of maintenance records indicated that no maintenance relevant to  ;

disk or seat integrity had been performed during the time period reviewed.

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5.4 Diesel Generator Fuel Oil Check Valves i

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The two diesel generator fuel oil transfer pump discharge check valves  ;

are forward flow tested when fuel oil is transferred to the day tank.

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The valves are not tested for.backleakage or inspected for disk and seat

integrity. However, with the va.lves in the cross connection piping locked )

closed, there did not appear to'be any reason to require testing for disk

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and seat integrity. A review of the maintenance records indicated that

no maintenance had been performed during the time period reviewed.

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5.5 Diesel Generator Air Start System Check Valves j

The two check valves coming from the air compressor to the air receiver

tank serve as the isolation boundary between the seismic Category I and j

Category II portions of the compressed air system. These valves are not i

tested to ensure that they will perform the isolation function. They are

only tested to pass flow. If a seismic event were to occur, failure of

these valves to isolate would result in the loss of air pressure necessary

to start the diesel generators. The licensee has stated that these valves

will be added to those tested under PET-14-2. The check valve on the A

diesel generator is installed with a 90* elbow attached to its inlet and ,

an isolation valve and a 90 elbow directly downstream. The check valve

on the B diesel generator is installed with the isolation valve 5 inches

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downstream of its outlet. A review of maintenance records indicated that

no maintenance of interest had been performed during the time period

reviewed.

5.6 Feedwater System (FW) Check Valves

Two stop check valves and two swing check valves (FW-2025 and FW-2026)

are located at the FW pump discharges. Flow from the pump discharge

passes through a 60* elbow to a 90 reducing elbow to the swing check valve.

Flow continues downstream through a 90* elbow attached to the stop check

valve, through the valve, and down a straight run of pipe. There are no

documented tests on these valves, although the valves pass flow during

normal operations. A review of the maintenance records indicated that no

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maintenance relevant to disk or seat integrity had been performed during

l the time period reviewed. The licensee has included these valves in the

l check valve reliability program.

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Check valves FW-2017, FW-2018, FW-2019, and FW-2020 are located in 14-inch

feedwater pipes just outside containment. These valves are-leak rate

tested. A review of the maintenance records indicated that only valve

FW-2019 had undergone maintenance during the period reviewed. Because of  ;

leakage past the valve, the valve disk and seat were lapped and retested

with a.cceptable results.

5.7 Fire Protection Check Valves

Check valves FP-2008 and FP-2009 are 10-inch valves attached to the fire

pump discharges. On the motor driven pump, the check valve outlet has I

a tee connected to it, with a gate valve connected to the outlet of the I

tee. On the diesel driven pump, the check valve outlet has a 90*. elbow

connected to it, with a gate valve, a' tee, a 906 elbow, and another gate i

valve following immediately after. These valves are not covered by a i

documented test but are observed to determine if they will pass flow when 1

the pumps are run. A review of the maintenance records indicated no l

maintenance relevant to disk or seat integrity had been performed during

the period reviewed. . ,

5.8 Instrument and Service Air Conta'inment Penetration Check Valves

The containment isolation valves for service air and instrument air are

tested for forward and reverse flow under the IST program.

Maintenan:e records indicated that in December 1979, the service air check )

valve was found rusted to the point that the valve was held in the open

position. The valve was cleaned and reassembled. At that time it was

brcught to the maintenance engineer's attention that possibly a different

type of valve was needed to ensure that rusting would not occur in the

future. In April 1980, rust was again found on the plus and seat of the i

service air check valve after the valve failed the local leak rate test. l

In March 1985, after the service air check valve failed local leak rate i

testing and experienced continued degradation, both the service air and

instrument air containment isolation check valves were replaced.

Three additional MRs from 1980 and 1981 were reviewed for these two

valves. The MRs identified minor internal and external leaking problems,

and the valves were repaired by lapping and repairing the seating surfaces.

5.9 Main Steam Check Valves

Check valves MS-2009, MS-2008, MS-2007, and MS-2006 are located in 3-inch

lines supplying steam to the AFW pump turbine. The valves are exercised

open using forward flow during operation of the turbine driven AFW pump and

verified closed by pressurizing the volume of piping dcwnstream of the

valves with air and monitoring the air pressure rate of decay. Furthermore,

the licensee plans to disassemble and visually inspect each of the valves

at least once every 5 years. A review of the maintenance records indicated

that all four valves had been disassembled and inspected in May 1966, after

a nut and washer were found in the AFW pump turbine trip and throttle. valve

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strainer The inspection revealed that the valve disk for valve MS-2009

was 'lyin in the bottom of the valve body. A new disk stud was installed,

and the ockwire on the disk retaining nut was replaced with a cotter

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pin. The disk stud in valve MS-2008 failed a penetrant test and was also

replaced. Cotter pins were substituted for the lockwires on valves MS-2006, '

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MS-2007, and MS-2008. Valve MS-2006 is installed 3 feet downstream of a

90* elbow, has a 90* elbow attached to its discharge, with a second 90*

elbow 1 foot downstream of it. Valve MS-2009 is installed 2 feet

downstream of a tee, with a 90* elbow 2 feet downstream of the valve.

. Yalve MS-2008 is installed with a 45 elbow attached to its inlet and a ,

l 90 elbow attached to its outlet. Valve MS-2007 is installed with a 90* i

elbow at its inlet and outlet.

Check valves MS-2001, MS-2002, MS-1003, and MS-2004 are located in the

28-inch main steam lines and are exercised open and closed during normal

l operations. The valves are located just downstream of the main steam

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isolation valves. A review of the maintenance records revealed that these

i valves had failed to close on several occasions. In May 1980, MS-2004 i

failed to close and all four valves were repacked under MR 80-1827.  !

In October 1982, valves MS-2001, MS-2002, and MS-2003 failed to close, and J

the packing was replaced and adjusted under MR 82-4064. In March 1983, i

all four valves failed to close and the packing was replaced and adjusted

under MR 83-1268. In September,1983, valve MS-2004 failed to close and the

packing was replaced and adjusted under MR 83-3283. Under NR 84-1582, the J

counterweight on HS-?004 was placed back on the valve after it had fallen

off. Unoer MR 86-0085, all four valves received their annually scheduled

repacking.

5.10 Residual Heat Removal (RHR) System Check Valves

Periodic Operating Test POT-16-1 is the inservice test for pumps and valves

in the RhR system. In addition to being the test for the RHR pumps, it is a

partial stroke inservice test for the RHR pump discharge check valves )

8730A and B. Paragraphs 7.1.7 and 7.2.7 of POT-16-1 note that satisfactory i

pump operation and flow indicate flow through the RHR pump discharge j

check valves. This satisfies the forward flow requirements of the l

IST program. Currently, no reverse flow testing is being performed, but

reverse flow testing has been recommended by licensee's reliability study

and is feasible for these valves. A review of the maintenance records I

indicated that no maintenance relevant to disk or seat integritl/ had been l

performed during the time period reviewed.

POT-2-6 is the inservice test performed on check valves 8818A, B, C,

and D. These valves are in the injection lines to the reactor coolant '

system (RCS) cold legs. The valves are tested for forward and reverse

flow with this procedure. Available records indicated that no maintenance

relevant to disk or seat integrity had been performed on the valves since

1980 and that the valves had not failed during the 1980-1987 period.

Valve 8958, which is located in the 14-inch pipe between the reactor

water storage tank (RWST) and the RHR pumps, is tested using POT-2-5. This

test is a forward flow test and is not included in the IST or Appendix J

testing programs. The two MRs that were available for valve 8958 indicated

that the valve experienced body to bonnet leaks and was repaired by

replacing the gasket in both 1982 and 1984.

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Check valves 8736A~ana B are the check valves in the 8-inch RHR discharge 1

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header to the RCS hot leg. These valves are in the IST program and are )

tested for forward and reverse flows using POT-2-6 and POT-2-4. Maintenance

records showed that valve 87368 had a bonnet to body leak in September 1986.

The repair consisted of torquing the bonnet nuts according to the vendor

technical manual. No other maintenance history existed for the valves.

5.11 Safety Injection (SI) System Check Valves

Valves 8948A, B, C, and D are included in the IST program and are tested

for forward and reverse flows using P0T-2-6 and POT-2-4. These 10-inch

valves are located in the common header of the SI system to the RCS. liRs

for valves 8948A and D identified leakage in 1983 and 1985, respectively.

8948A was repaired by machining a new bonnet. The internals of valve  ;

0948D were inspected and the gasket was replaced. No other maintenance

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! The following check valves located in the SI system were reviewed to

determine whether they were inc1W in the IST or Appendix J testing

programs and what types of testipg were being performed on the valves.

No maintenance history relevant'to disk or seat integrity existed for

these valves during the 1980-1987 period.

Valves 8956A, b, C, and D are 10-inch valves located in the line from l

the accumulators to the RCS cold legs. They are in the IST program and  !

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are tested for forward and reverse flow.

Valve 8968 is tested under the Appendix J program and is located in the

1-inch line from the nitrogen supply to the accumulators.

P0T-2-6 is used to test forward flow in valve 8926 from the RWST to the

SI pumps. No reverse flow testing is performed. 1

The SI aump discharge check valves, 8922A and B, are forward flow tested

under t1e IST program, but not reverse flow tested. Reverse flow testing

is being considered in the licensee's reliability study. An in-plant

inspection of the check valves and piping up and downstream of the valves

was performed. Directly upstream of the check valve is a tee preceded by

a 90* elbow attached to the SI pump. An isolation valve that is 1 foot

downstream of the check valve is followed by a 90* elbow 1 additional foot

downstream. This configuration exists for both valves 8922A and B.

Safety injection line check valves to both the RCS cold and hot legs are

forward and reverse flow tested using POT-2-6 and POT-2-4. These IST program

check valves include 8819A, B, C, and D and 8905A, B, C, and D.

Check valve 8815 is located in the line coming from the Boron Injection

Tank (blT) and is full flow tested using POT-2-6. No reverse flow testing

is performed.

Check valves 8949A, B, C, and D are 6-inch valves located between the

SI arid RHR pumps and the RCS hot leg. These valves are in the IST program

and 'are tested for forward and reverse flow using POT-2-6 and POT-2-4.

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le 5.12 Service Water (SW) Check Valves

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Check valves SW 2008, 2009, 2010, and 2011 are the check valves located

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in the line that supplies lubricating water to the SW pump bearings. These

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valves are not in the IST or Appendix J testing programs and are not tested

for forward or reverse flow. The decision not to test these valves was

based on correspondence with the pump vendor confirming that the SW pumps

can operate long term without lubricating water flow. There is no

maintenance history for these valves.

POT-5-1 is used in testing check valves SW 2019, 2020, and 2021 by taking

temperature readings. These valves include the SW supply to the diesel

driven AFW pump lubricating oil heat exchanger' the SW cutlet from the

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diesel driven AFW pump lubricating oil heat exchanger, and the SW supply

to the diesel driven AFW pump gear cooler. These valves are not tested /

under the IST or Appendix J testing programs, and no maintenance history I

existed. '

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Valve SW 2022 is forwar'd flow tested under the IST Program. This check )

valve is in the outlet from the/ diesel driven AFW pump cooler. There is '

no current maintenance history on this valve. No reverse flow or

Appendix J testing is performed.

! 5.13 Service Water Booster Pump (SWBP) Discharge Check Valves

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Forward flow for valves SW 2014, 2015, 2023 and 2024 is tested by using

POT-7-3. These valves are part of the IST program and are also tested to

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verify reseating.

l Maintenance history indicated that in June 1983, the SWBP discharge check

, valves (2014 and 2015) exhibited a problem in that the counterbalance

l arm was loose and rotated freely 360 . Also in June 198S, the positive

I. displacement pump check valve, SW 2025, counterweight arm was found to

rotate freely 360 . New key ways and hinge pins were installed on the

! valves. There has been no niaintenance history on these valves since 1983.

Valves SW 2014, 2015, 2023, and 2024 were inspected during the plant

walkdown. Each of the four check valves is installed directly after b

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90 elbow from the SWBP. A butterfly valve, 90 elbow, and tee are

downstream of the check valve.

5.14 Service Water (SW) Pump Discharge Check Valves

Valves SW 2003, 2004, and 2005 are included in the IST program. These

check valves are tested in accordance with POT-7-1 for forward flow. No

reverse flow testing is performed; however, the licensee has initiated

preventive maintenance, and each valve is being inspected every 3 years-

The maintenance history for these valves indicated that on January 3, 1983,

all three valves were repaired. Valve SW 2003 received new springs and

bushings and a new hinge shaft. SW 2004 was removed and the worn springs

l and, hinge shaft were replaced. When valve SW 2005 was inspected, it was

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discovered that the hinge spring from the valve was broken and the spring

fjnger was later found in a strainer. New bearings and spacers were installed.

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These check valves were examinea during the in-plant inspection. Check-

valves SW 2003 and 2004'were installed vertically after a 90* elbow  ;

at the SW punp discharge. Downstream of the valves, a butterfly valve and

tee led to a common header which led to a 90' elbow. Valve SW 2005 was

installed the same way, except there was not a 90 elbow downstream of the i

common header.

6.0 Exit fleeting

The inspectors met with licensee management representatives noted in Section .

1 on May 21, 1987. The scope of the inspection and the inspection findings .I

l in this report were discussed. ,

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