Information Notice 1987-08, Degraded Motor Leads in Limitorque DC Motor Operators

Degraded Motor Leads in Limitorque DC Motor Operators

ML031140345
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, Skagit, Marble Hill
Issue date:	02/04/1987
From:	Jordan E NRC/IE
To:
References
IN-87-008, NUDOCS 8702020135
Download: ML031140345 (6)

SSINS No.: 6835 IN 87-08 UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF INSPECTION AND ENFORCEMENT

WASHINGTON, D.C. 20555 February 4, 1987 IE INFORMATION NOTICE NO. 87-08: DEGRADED MOTOR LEADS IN LIMITORQUE DC

MOTOR OPERATORS

Addressees

All nuclear power reactor facilities holding an operating license (OL) or a

construction permit (CP).

Purpose

This notice is provided to alert recipients of potentially defective dc motors

installed in Limitorque motor operators. The motors in question were manu- factured at H. K. Porter (now Peerless-Winsmith) between December 1984 and

December 1985. The motors are fitted with Nomex-Kapton insulated leads that

are susceptible to insulation degradation and subsequent short circuit failure.

The Nomex-Kapton leads are different than the leads which were tested and

reported in Limitorque Qualification Report B-0009 dated April 30, 1976. Valves

with these Nomex-Kapton leads have recently failed to actuate on demand at two

nuclear plant sites. It is expected that recipients will review this informa- tion for applicability to their facilities and consider actions, if appropriate, to preclude a similar problem from occurring at their facilities. However, suggestions contained in this notice do not constitute NRC requirements;

therefore, no specific action or written response is required.

Description of Circumstances

On May 6, 1986 the NRC received from Portland General Electric Company a

10 CFR 21 report concerning a motor failure which occurred at its Trojan

Nuclear Power Plant. The failure involved shorting of the motor leads inside

a Limitorque motor operator connected to an auxiliary feedwater flow control

valve. Upon inspection it was determined that the failure was the result of

insulation degradation of the motor leads that had allowed two leads to short

together. Further, inspection at Trojan revealed three similar motors that

also had experienced insulation degradation.

Recently, the NRC has also learned of a failure at the Turkey Point Nuclear

Power Plant in which the steam supply valve for the auxiliary feedwater turbine

failed to operate after a Limitorque motor operator experienced a similar motor

lead short circuit. The Trojan and the Turkey Point Limitorque operators

were found to contain motors manufactured with Nomex-Kapton insulated leads.

IN 87-08 February 4, 1987 On January 12-14, 1987, the NRC conducted an inspection at Peerless-Winsmith, Inc., manufacturer of dc motors for Llmitorque Co. During this inspection it

was determined that the failed Nomex-Kapton leads were different than the

leads which were fitted to the motors, tested, and documented in Limitorque

Qualification Report B-0009 for dc motor operators. The leads attached to the

tested motors were insulated with Nomex plus an epoxy impregnated braided fiber- glass sleeve. The NRC knows of no analysis or testing that has been performed

to show the Nomex-Kapton leads are acceptable for use in an application requir- ing environmental qualification. Further, it should be noted that the failures

cited above occurred under normal operating conditions, not under the harsh

conditions which could occur in areas where environmental qualification is

required.

On December 19, 1986, Limitorque notified 30 plant sites (Attachment 1) that

had received affected motors and recommended the sleeving of existing Nomex- Kapton motor leads. The sleeving system is still under development and

Limitorque expects to have this system tested for environmental qualification

by the third quarter of 1987.

Discussion:

The Peerless-Winsmith motors were manufactured between December 1984 and

December 1985 and can be identified by the first two letters of the serial

number data code on the motors. Motor serial numbers beginning with the

letters ZM, NN, PN, QN, RN, SN, TN, UN, VN, WN, XN, YN, and ZN likely contain

the Nomex-Kapton leads. The lead insulation consists of one layer of 50 percent

overlapped 0.003 inch Nomex plus a 50 percent overlapped layer of 0.0012 inch

F616 Kapton/FEP. This insulation system is about one-sixth the thickness of

the leads which were part of the Limitorque qualified motor. Peerless-Winsmith

has since switched to a third type of insulated lead similar to the ones used

originally. No failures with this type of lead have been reported; however, qualification of this type wire also needs to be ensured.

Previous, unrelated problems involving wiring installed in Limitorque motor

actuators have been identified in Information Notices 83-72, 86-03 and 86-71.

Although no written response to this notice is required, it is expected that

holders of OLs or CPs will review the information in this notice for applica- bility at their facilities. Because of the failures such as those discussed

above and the lack of demonstrated environmental qualification, NRC's evalua- tion of this problem is continuing. Depending on the results of the evaluation, specific actions may be requested. If you have any questions regarding this

IN 87-XX

January XX, 1987 above and the lack of demonstrated environmental qualification, NRC's evalua- tion of this problem is continuing. Depending on the results of the evaluation, specific actions may be requested. If you have any questions regarding this

matter, please contact the Regional Administrator of the appropriate NRC

Regional Office, or this office.

Edward L. Jordan, Director

Division of Emergency Preparedness

and Engineering Response

Office of Inspection and Enforcement

Contact: J. Jacobson, IE

(301) 492-8845 Attachments:

1. List of Affected Plants

2. List of Recently Issued IE Information Notices

• SEE PREVIOUS PAGE FOR CONCURRENCE

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Attachment 2 IN 87-07 February 3, 1987 LIST OF RECENTLY ISSUED

IE INFORMATION NOTICES

Information Date of

Notice No. Subject Issue Issued to

87-07 Quality Control of Onsite 2/3/87 All power reactor

Dewatering/Solidification facilities holding

Operations by Outside an OL or CP

Contractors

87-06 Loss of Suction to Low- 1/30/87 All power reactor

Pressure Service Water facilities holding

System Pumps Resulting From an OL or CP

Loss of Siphon

87-05 Miswiring in a Westinghouse 2/2/87 All Westinghouse

Rod Control System power reactor

facilities holding

an OL or CP

87-04 Diesel Generator Fails 1/16/87 All power reactor

Test Because of Degraded facilities holding

Fuel an OL or CP

87-03 Segregation of Hazardous 1/15/87 All NRC licensees

87-02 Inadequate Seismic Quali- 1/15/87 All power reactor

fication of Diaphragm facilities holding

Valves by Mathematical an OL or CP

Modeling and Analysis

87-01 RHR Valve Misalignment 1/6/87 All PWR facilities

Causes Degradation of holding an OL or CP

ECCS in PWRs86-110 Anomalous Behavior of 12/31/86 All BWR facilities

Recirculation Loop Flow holding an OL or CP

in Jet Pump BWR Plants86-109 Diaphragm Failure In Scram 12/29/86 All BWR facilities

Outlet Valve Causing Rod holding an OL or CP

Insertion

86-108 Degradation Of Reactor 12/29/86 All PWR facilities

Coolant System Pressure holding an OL or CP

Boundary Resulting From

Boric Acid Corrosion .

OL = Operating License

CP = Construction Permit

IN 87-XX

January XX, 1987 NRC's evaluation of

and the lack of demonstrated environmental qualification, of the evaluation, this problem is continuing. Depending on the results

any questions regarding this

specific actions may be requested. If you have appropriate NRC

matter, please contact the Regional Administrator of the

Regional Office, or this office.

/

Edward L. Jordan, Division of Emer,

,*9 Response

xction and Enforcement

Contact: J. Jacobson, IE

(301) 492-8845 Attachments:

1. List of Affected Plants

2. List of Recently Issued IE Information ces

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Attachment 1 IN 87-08 February 4, 1987 LIST OF LIMITORQUE CUSTOMERS AND ASSOCIATED

NUCLEAR POWER FACILITIES

WHICH HAVE RECEIVED AFFECTED MOTOR OPERATORS

Limitorque Customer Associated Facility

Anchor Darling E. I. Hatch

Anchor Darling Clinton

Arkansas Power & Light Company Arkansas Nuclear One #1 Bechtel Power Corporation Pilgrim

Bechtel Power Corporation Limerick

Boston Edison Pilgrim

Carolina Power & Light Company Brunswick

Carolina Power & Light Company Brunswick

Cleveland Electric Illuminating Company Perry

Combustion Engineering Palo Verde

Commonwealth Edison Company LaSalle

Detroit Edison Company Fermi 2 Florida Power Corporation Crystal River

Florida Power & Light Company Turkey Point

GPU Nuclear Corporation Oyster Creek

Gulf States Utilities River Bend

Iowa Electric Light & Power Duane Arnold Energy Center

Mississippi Power & Light Grand Gulf

Nebraska Public Power Cooper

Northeast Nuclear Energy Millstone

Pennsylvania Power & Light Susquehanna SES

Philadelphia Electric Company Peach Bottom

Portland General Electric Company Trojan

Posi-Seal International Inc. Susquehanna SES

Public Service Electric & Gas Hope Creek

Rockwell International Inc. South Texas Project

Southern California Edison San Onofre

Tennessee Valley Authority Browns Ferry

Tennessee Valley Authority Browns Ferry

Union Electric Company Callaway

Velan, Inc. Nine Mile Point

Washington Public Power Supply System WNP-2 William Powell Company Grand Gulf

NOTE: Limitorque records indicate that motor operators with the suspect

leads have been shipped to the nuclear power plants listed above. However, failure to be listed should not be considered as assurance that a plant has

not received operators with Nomex-Kapton leads.