Information Notice 1988-59, Main Steam Isolation Valve Guide Rail Failure at Waterford Unit 3

Main Steam Isolation Valve Guide Rail Failure at Waterford Unit 3

ML031150013
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	08/09/1988
From:	Rossi C Office of Nuclear Reactor Regulation
To:
References
IN-88-059, NUDOCS 8808030112
Download: ML031150013 (8)

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 August 9, 1988 NRC INFORMATION NOTICE NO. 88-59: MAIN STEAM ISOLATION VALVE GUIDE RAIL

FAILURE AT WATERFORD UNIT 3

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors.

Purpose

This information notice discusses a main steam isolation valve (MSIV) guide

rail failure at Waterford 3 and its possible generic implications. The MSIV

is a D-2 Power Seal type, manufactured by ACF Industries, WKM Valve Division.

It is expected that recipients will review the information for applicability

to their facilities and consider actions, as appropriate, to avoid similar

problems. However, suggestions contained in this information notice do not

constitute NRC requirements; therefore, no specific action or written response

is required.

Description of Circumstances

On April 11, 1988, during a routine inspection at Waterford 3, MSIV debris was

found in the strainer for the main turbine throttle valve. The disassembly and

inspection of the two MSIVs at the plant revealed that the downstream guide

rails in one of the valves (see attached drawing) had become completely dis- lodged, and several bolt heads on the still-attached upstream rails in the same

valve had been completely severed. The other MSIV had several separated bolt

heads on both upstream and downstream rails, but the guide rails were in place.

There were also galling marks on the chamfer of the guide rail and on the shoe

attached to the lever lock arm.

Discussion:

An analysis by the licensee indicates that the guide rail failure was caused by

the force of the lever lock arm assembly contacting the rail. The valve, however, passed the inservice test requirements. The analysis concludes that

even without the rails the valve could still perform its function, albeit at a

closure time that is slower by about a second, under the worst-case condition.

However, there is a possibility that a detached rail could jam the MSIV in a

partially open position. The failure of one MSIV is accounted for in the

utility's Safety Analysis Report.

8808030112 ZA

IN 88-59 August 9, 1988 After the failure at Waterford 3, a fiberscope examination of the WKM power

seal MSIVs at San Onofre Unit 3 revealed a broken bolt lying in the bottom

section of the body of one MSIV. Disassembly and inspection of this valve

revealed three failed bolts, galling marks on the shoe and the chamfer, and

an upstream rail slightly detached from the skirt plate. At the same plant, a shutdown cooling isolation valve of a similar design was also damaged. How- ever, the licensee believes that this damage occurred during maintenance. The

damage was similar to that found on the MSIVs, that is, galling marks, failed

bolts, and detached rails, but, in addition, the skirt plate was fractured and

the shoe was wedged into the lever arm pivot slot.

The NRC believes this type of failure could be generic to other plants. Valves

of this type are also reported to be in use at San Onofre 2, South Texas 1 and 2, and Washington Nuclear Power Unit 2. Valves of similar design could exist at

other plants. The preliminary indications suggest that the failures are

attributable to deficiencies in fabrication, engineering, and materials. The

corrective actions considered at Waterford and San Onofre 3 include

(1) stelliting the shoes and the chamfer on the rails

(2) verifying the bolt alignments

_doingnondestructive examinations of all new bolts

__ _ _ _-1-- ' . t -.------- - -. __

, ._

__ ___ __

(4) changing the angles of the rails and of the shoes

(5) increasing the valve closure time (within system performance constraints)

(6) periodically making fiberscope examinations of the valve internals

to detect excessive galling, severed guide rail bolts, and separated

guide ra'ls

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the technical

contact listed below or the Regional Administrator of the appropriate regional

office.

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Kenneth Dempsey, NRR

(301) 492-0918 Attachments:

1. Figure of Valve

2. List of Recently Issued NRC Information Notices

Attachment

IN 88-59 August 9, 1988 Page I of

GATE S SEGMENT

ASSEMBLY

GUIDE RAIL BOLT

LOCATIONS (9 PER

GUIDE RAIL). TYPICAI

OF 4 GUIDE RAILS

1-' Atti nt 2 in 88-59 August 9. 1988 Page 1 of I

LIST oF RECEaIMT ISSUED

NRC INFOidATION NOTICES

_AA--- n-.-

UtU UT

rreson"At1nr

iaiWowb

Notice No. SubJect Issuance Issued to

Potential Problems with 8/8/88 All holders of uLs

AScA 8rown toverl ITE-s1L or CPs for nuclear

Time-Overcurrent Relays power reactors.

88-57 Potential Loss of Safe 8/3/88 All holders of OLs

Shutdown Equipment Due to or CPs for nuclear

Preesture Silicon Controlled power reactors.

Rectifier Failure

de-Sd Potential Problems with 8/4/88 All holders of OLs

Silicone Foas Fire Barrier or CPs for nuclear

Penetration Seals power reactors.

Potential Problem Caused WM/8 All holders of OLs

by Single Failure of an or CPS for nuclear

88-55 Engineered Safety Feature power reactors.

Swing tus

Failure of Circuit Breaker 7/28/88 All holders of OLs

Following Installation of or CPS for nuclear

Amptector Direct Trip power reactors.

AttacJment

88-54 Licensee Violations of NRC 7/28/88 All manufacture and

Regulations, Which Led to distributors of radio- ledical Diagnostic pharmaceuticals for

Misadvinistrations hum use. nuclear

pharmacies, and

medical licensees.

88-52 Failure of Intrauterine 7/27/88 Medical licensees.

Tandem of Fletcher

Applicator Irachytherapy

Deuces During Patient

Treatment

81-46. -- ticense- Report of - - 7/26/88- - All hol40dsof-Ls

Supplement 1 Cefective Refurbished or CPs for nuclear

Circuit Breakers power reactors.

OL

• Op rating License

CP

• Construction Permit

UNITED STATES FIRST CLSSMAIL1 IPOSTAGE &FEES PAIDI

NUCLEAR REGULATORY COMMISSION IUSNRCI

WASHINGTON, D.C. 20555 OFFICIAL BUSINESS

PENALTY FOR PRIVATE USE. $300

IN 88-59 August 9, 1988 After the failure at Waterford 3, a fiberscope examination of the WKM power

seal MSIVs at San Onofre Unit 3 revealed a broken bolt lying in the bottom

section of the body of one MSIV. Disassembly and inspection of this valve

revealed three failed bolts, galling marks on the shoe and the chamfer, and

an upstream rail slightly detached from the skirt plate. At the same plant, a shutdown cooling isolation valve of a similar design was also damaged. How- ever, the licensee believes that this damage occurred during maintenance. The

damage was similar to that found on the MSIVs, that is, galling marks, failed

bolts, and detached rails, but, in addition, the skirt plate was fractured and

the shoe was wedged into the lever arm pivot slot.

The NRC believes this type of failure could be generic to other plants. Valves

of this type are also reported to be in use at San Onofre 2, South Texas 1 and 2, and Washington Nuclear Power Unit 2. Valves of similar design could exist at

other plants. The preliminary indications suggest that the failures are

attributable to deficiencies in fabrication, engineering, and materials. The

corrective actions considered at Waterford and San Onofre 3 include

(1) stelliting the shoes and the chamfer on the rails

(2) verifying the bolt alignments

(3) doing nondestructive examinations of all new bolts

(4) changing the angles of the rails and of the shoes

(5) increasing the valve closure time (within system performance constraints)

(6) periodically making fiberscope examinations of the valve internals

to detect excessive galling, severed guide rail bolts, and separated

guide rails

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the technical

contact listed below or the Regional Administrator of the appropriate regional

office.

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Kenneth Dempsey, NRR

(301) 492-0918 Attachments:

1. Figure of Valve

2. List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCES

• C/OGCB:DOEA:NRR *RPB:ARM

Rossi i CHBerlinger TechEd

08/3 /88 08/01/88 07/27/88

• OGCB:DOEA:NRR *EMEB:DEST:NRR *C/EMEB:DEST:NRR *EAD/DEST:NRR *D/DEST:NRR

DCKirkpatrick KDempsey LBMarsh JRichardson LCShao

07/26/88 07/28/88 07/29/88 07/29/88 07/29/88

IN 88-XX

July xx, 1988 After the failure at Waterford 3, a fiberscope examination of the WKM power

seal MSIVs at San Onofre Unit 3 revealed a broken bolt lying in the bottom

section of the body of one MSIV. Disassembly and inspection of this valve

revealed three failed bolts, galling marks on the shoe and the chamfer, and an

upstream rail slightly detached from the skirt plate. At the same plant, a

shutdown cooling isolation valve of a similar design was also damaged. How- ever, the licensee believes that this damage occurred during maintenance. The

damage was similar to that found on the MSIVs, that is, galling marks, failed

bolts, and detached rails, but, in addition, the skirt plate was fractured and

the shoe was wedged into the lever arm pivot slot.

NRC believes this type of failure to be generic to other plants. Valves of

this type are also reported to be in use at San Onofre 2, South Texas 1 and 2, and Washington Nuclear Power Unit 2. Valves of similar design could exist at

other plants. The preliminary indications suggest that the failures are

attributable to deficiencies in fabrication, engineering, and materials. The

corrective actions considered at Waterford and San Onofre 3 include

(1) stelliting the shoes and the chamfer on the rails

(2) verifying the bolt alignments

(3) doing nondestructive examinations of all new bolts

(4) changing the angles of the rails and of the shoes

(5) increasing the valve closure time (within system constraints)

(6) periodically making fiberscope examinations of the valve internals to

detect excessive galling, severed guide rail bolts, and separated

guide rails

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the technical

contact listed below or the Regional Administrator of the appropriate regional

office.

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Kenneth Dempsey, NRR

(301) 492-0918 Attachments:

1. Figure

2. List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCES C021 D/DOEA:NRR C/OGCB:DOEA:NRR *RPB:ARM

CERossi CVBerlinger TechEd

07/ /88 0 6)/88 07/27/fM'tA

• OGCB:DOEA:NRR EMEB4REST:NRR C/EMEB:DEST:NRR EAD/DEST: D/DES h

DCKirkpatrick KD f y LBMarsh JRichards nr/zn LCShao

07/26/88 07/..2/88 vj 7/88 07/J '/88 07, /88

IN 88-XX

July xx, 1988 Subsequent-to the failure at Waterford 3, a fiberscope examination of the WKM

h power seal MSIVsit -an Onofre9Jnit 3 revealed a roken bolt lying in the

bottom section of the body of one MSIV. 4umiang/i assembly and inspection of

-was-foUlU-te-hes e three failed bt5, galling marks on the shoe

and the c imfer, and an upstream rail slightly detached from the skirt plate.

At the same plant, a shutdown cooltng isolation valve of a similar design was

also fewnd-te-be9 damaged. However, the licensee believes that this damage

J c ncurred during maintenance. The damage was similar to that found on the

/MSI1iV4%e4_galling marks, failed bolts, and detached rails, but, in addition,

,Ythe skirt plate was fractured and the shoe was wedged into the lever arm pivot

S g slot. t a PL

Cjhis type of failure 44-be+eved to be generic to other plants. Valves-of

n this type are also eported to be in use at San Onofre 2, South Texas 1 and 2,

7iand-0.SL Valve similar 'nkdesigncould exist at other plants. The pr~imi- cat ons that the failures are attributable to deficien sn

fabricaton, t en I eering, and materials. The corrective actions t-have-ten"er

considered at Waterford and San Onofre 3 includeiL,/

qQS8x;A F-J(1,V Xtelliting the shoes and the chamfer on the rai ,-r

,* ~ (2,).erifying the bolt alignmentsa--

=LT73-) 4Voing nondestructive examinations of all ne bolts,-

u(4j)4hanglng the angles of the rails and of t shoes,.

//It" fl 75i) .ncreasing the valve closure time (withi system constraints),.->

i !U..'6)Ieriodicallymaking fiberscope examina ions of the valve internals to

J, e- detect excessive galling, severed gu e rail bolts, and separated

'3/4.8 Sguide rails.--- i by

No specific action or written response sequired by thia/i nformation notice. -

Ifyou have any questions about this mat er, please ci&fiet-the technical

contact listed below or the,,,egional inistrator of the appropriate regional

office.

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Kenne Dempsey, NRR

(30 492-0918 Attachments:

1. Figure

2. List of Recentl Issued NRC Information Notices

D/DOEA:NRR C/OGCB:DOEA:NRR RFA':

CERossi CHBerlinger WchO1fW/88

07/ /88 07/ /88 07/o77/88 OGCB:DOEA:NRR EM BDB T:NRR C/EMEB:DEST:NRR EAD/DEST:NRR D/DEST:NRR

DCKirkpatjjjl KDipb6j' LBMarsh JRichardson LCShao

07/g;/88 AJW# 07/ 7 ~f88 07/ /88 07/ /88 07/ /88

IN 88-XX

July xx, 1988 Subsequent to the failure at Waterford 3, a fiberscope examination of the WKM

power seal MSIVs at San Onofre'Unit 3 revealed a broken bolt lying in the

bottom section of the body of one MSIV. During disassembly and inspection of

this valve, it was found to have three failed bolts, galling marks on the shoe

and the chamfer, and an upstream rail slightly detached from the skirt plate.

At the same plant, a shutdown cooling isolation valve of a similar design was

also found to be damaged. However, the licensee believes that this damage

occurred during maintenance. The damage was similar to that found on the

MSIVs, i.e., galling marks, failed bolts, and detached rails, but, in addition, the skirt plate was fractured and the shoe was wedged into the lever arm pivot

slot.

This type of failure is believed to be generic to other plants. Valves of

this type are also reported to be in use at San Onofre 2, South Texas 1 and 2, and WPPS. Valves similar in design could exist at other plants. The prelimi- nary indications are that the failures are attributable to deficiencies in

fabrication, engineering, and materials. The corrective actions that have been

considered at Waterford and San Onofre 3 include:

1. Stelliting the shoes and the chamfer on the rails,

2. Verifying the bolt alignments,

3. Doing nondestructive examinations of all new bolts,

4. Changing the angles of the rails and of the shoes,

5. Increasing the valve closure time (within system cons raints),

6. Periodically making fiberscope examinations of the alve internals to

detect excessive galling, severed guide rail bolt, and separated

guide rails.

No specific action or written response is required by is information notice.

If you have any questions about this matter, please ontact the technical

contact listed below or the Regional Administrator f the appropriate regional

office.

Charl E. Rossi, Director

Div ion of Operational Events Assessment

Of ce of Nuclear Reactor Regulation

Kenneth Dempse NRR

(301) 492-09 Attachments:

1. Figure

2. List of Recently Issue NRC Information Notices

D/DOEA:NRR C/OGCB:DOEA:NRR RPB:ARM

CERossi CHBerlinger TechEd

07/ /88 07/ /88 07/ /88 OGCB:DOEA:NRR EMEBL:DIST:NRR C/EMEB:DEST:NRR EAD/DEST:NRR D/DEST:NRR

DCKirkpaty4gI KDOW%~y LBMarsh JRichardson LCShao

07/;I$/88 AJw 07D-8/88 07/ /88 07/ /88 07/ /88