Information Notice 1996-46, Zinc Plating of Hardened Metal Parts and Removal of Protective Coatings in Refurbished Circuit Breakers

Zinc Plating of Hardened Metal Parts and Removal of Protective Coatings in Refurbished Circuit Breakers

ML031060109
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, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	08/12/1996
From:	Grimes B Office of Nuclear Reactor Regulation
To:
References
IN-96-046, NUDOCS 9608090035
Download: ML031060109 (7)

KY

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555-0001 August 12, 1996 NRC INFORMATION NOTICE 96-46: ZINC PLATING OF HARDENED METAL PARTS AND

REMOVAL OF PROTECTIVE COATINGS IN REFURBISHED

CIRCUIT BREAKERS

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information

notice to alert addressees that inadequate licensee review of procedures

employed by a circuit breaker refurbishing contractor resulted in breakage of

hardened metal parts and potentially increased wear of other metal parts that

could cause the refurbished breakers to fail to operate. 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 are not NRC requirements;

therefore, no specific action or written response is required.

Description of Circumstances

In May 1996, technicians employed by Public Service Electric & Gas (PSE&G) at

its Salem Generating Station (Salem) observed broken lock washers in the arc

chute holddown assembly of a General Electric (GE) 4.16-kV AM-type Magne-Blast

circuit breaker during a receipt inspection. Nuclear Logistics Incorporated

(NLI), a breaker refurbishing contractor, refurbished the breaker. NLI used a

subcontractor, National Switchgear Systems (NSS), to perform the

refurbishment. The licensee determined that NSS did not remove or mask the

lock washers during the zinc-plating of the arc chute holddown assembly.

On July 16, 1996, during preinstallation testing of another Magne-Blast

breaker, technicians at Salem noted that the inner latch pawl spring retainer

roll pin of the spring charging mechanism was broken longitudinally. The pin

had been zinc plated during refurbishment at NSS. Failure of the pin may

cause the failure of the spring charging mechanism to charge the sprin,, and

cause the breaker to fail to operate on demand (open or close). However, if

the springs were charged when the breaker was closed, failure of the pin would

not prevent the breaker from opening.

9608090035 PDR IVE Not;C 94oZL

IN 96-46 August 12, 1996 Discussion

Low and medium voltage circuit breakers are refurbished periodically to assure

reliable operation by implementing manufacturer maintenance recommendations.

This service may be performed by the original manufacturer or by contractors

who implement a quality assurance program that meets 10 CFR Part 50,

Appendix B for safety-related equipment. In addition to establishing and

maintaining an acceptable licensee/vendor interface program to remain current

with manufacturer maintenance recommendations (in accordance with Generic

Letters 83-28 and 90-03), licensees are expected to assure that vendors (or

contractors) translate manufacturer recommendations into their procedures.

To enhance the appearance of some metal parts, NLI/NSS plated them with zinc

without realizing that hydrogen generated during the plating process can

diffuse into hardened metal parts. The diffusion of hydrogen into the

hardened metal may cause embrittlement and result in cracking and breakage of

the metal if heat treatment is not applied to desorb the hydrogen. Subsequent

to problems identified at Salem, NLI deleted the zinc plating of metal parts

from its breaker refurbishment procedure.

During an inspection at NLI, the NRC determined that NLI/NSS refurbished

various types of low and medium voltage circuit breakers used in the nuclear

power industry, including 4.16-kV and 480 V breakers made by GE and

Westinghouse. In addition to the GE Magne-Blast breakers at Salem, NLI/NSS

also plated several parts in a Magne-Blast breaker for Entergy Operations, Inc, GE model AK breakers for Northeast Utilities Company, and a Westinghouse

DB-50 breaker for Carolina Power & Light Company. Work also was done for GPU

Nuclear Corporation.

NLI has informed affected customers that the breakers with the identified

zinc-plated parts should be returned to NLI so that the parts can be replaced.

However, the NRC is concerned that NLI/NSS may not have identified all of the

zinc-plated parts in all of the different breakers that it refurbished because

the zinc-plating was performed on assemblies consisting of several smaller

piece parts. Some of the piece parts may not have been identified. NLI is

currently evaluating the implications of the plated parts and removal of the

dry film lubricant on other projects.

Technicians at Salem also noticed that some metal parts on GE-refurbished

breakers appeared darker than similar parts in the NLI/NSS-refurbished

breakers. Upon inquiry, GE informed Salem that the darker color resulted from

a dry film lubricant that GE applied to the parts to reduce wear between

metal-to-metal contact surfaces in accordance with GE Service Advisory Letter

(SAL) 354.1, "Lubrication Recommendations Type AM Circuit Breakers ML13 & ML

13A Mechanisms,' dated August 25, 1995, which states, in part, "And finally, a

spray-on, MoS (molybdenum disulfide) dry film lubricant is also being made

available, and it is recommended for use during general overhaul maintenance

periods to lubricate certain hardened surfaces."

IN 96-46 August 12, 1996 The dry film lubricant is applied to the following parts: (1) the ratchet

wheel, (2) the latch pawl tips, (3) the drive pawl tip, (4) the front and top

surfaces of the prop, (5) the main cam outer surface, and (6) the spring motor

limit switch cam. NLI/NSS inadvertently removed this lubricant when the metal

parts were glass bead blasted as part of the cleaning process, and did not re- coat the parts with the lubricant.

The work performed by NLI/NSS was detailed in a procedure that was reviewed

and approved by PSE&G prior to refurbishment of any of the Salem breakers.

Ensuring that contractor procedures receive proper technical review, and that

the latest vendor recommendations are incorporated before the procedures are

approved, may help licensees avoid the type of problems described in this

notice.

Related Generic Communications

NRC Generic Letter No. 83-28, "Required Actions Based on Generic Implications

of Salem ATWS Events,' issued July 8, 1983.

NRC Generic Letter No. 90-03, 'Relaxation of Staff Position in Generic Letter 83-28, Item 2.2 Part 2 - Vendor Interface for Safety-Related Components,"

issued March 20, 1990.

NRC Generic Letter No. 90-03, Supplement 1, "Relaxation of Staff Position in

Generic Letter 83-28, Item 2.2 Part 2 - Vendor Interface for Safety-Related

Components,' issued May 14, 1990.

NRC Information Notice 96-43, 'Failures of General Electric Magne-Blast

Circuit Breakers," issued August 2, 1996, alerted licensees to a failure of a

Magne-Blast breaker to open on demand at Dresden Nuclear Power Station because

of hardened grease, and a failure of Magne-Blast breakers at Salem Generating

Station and Maine Yankee Atomic Power Plant to latch closed because of a

problem with the prop not resetting under the prop pin during the closing

cycle.

i ul

IN 96-46 August 12, 1996 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Acting Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: David Skeen, NRR

('01) 415-1174 E-mail: dls@nrc.gov

Kamalakar Naidu, NRR

(301) 415-2980

E-mail: krn@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

- @ ^

Attachment

IN 96-46 August 12, 1996 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

96-45 Potential Common-Mode 8/12/96 All holders of OLs or CPs

Post-Accident Failure of for nuclear power reactors

Containment Coolers

96-44 Failure of Reactor 8/05/96 All holders of OLs or CPs

Trip Breaker from Cracking for nuclear power reactors

of Phenolic Material in

secondary contact assembly

96-43 Failures of General 08/02/96 All holders of OLs or CPs

Electric Magne-Blast for nuclear power reactors

Circuit Breakers

96-42 Unexpected Opening of 08/05/96 All holders of OLs or CPs

Multiple Safety Relief for nuclear power reactors

Valves

96-41 Effects of a Decrease in 07/26/96 All holders of OLs or CPs

Feedwater Temperature on for pressurized water

Nuclear Instrumentation reactors

96-40 Deficiencies in Material 07/25/96 All holders of OLs or CPs

Dedication and Procurement for nuclear power reactors

Practices and in Audits of

Vendors

96-09, Damage in Foreign Steam 07/10/96 All holders of OLs or CPs

Supp. 1 Generator Internals for pressurized-water

reactors

96-39 Estimates of Decay Heat 07/05/96 All holders of OLs or CPs

Using ANS 5.1 Decay Heat for nuclear power reactors

Standard May Vary Signi- ficantly

96-38 Results of Steam Generator 06/21/96 All holders of OLs or CPs

Tube Examinations for pressurized water

reactors

96-37 Inaccurate Reactor Water 06/18/96 All pressurized water

Level Indication and Inad- reactor facilities holding

vertent Draindown During an operating license or a

Shutdown construction permit

OL - Operating License

CP = Construction Permit

-

IN 96-46 August 12, 1996 This information notice requires no specific action or written response.

you have any questions about the information in this notice, please If

one of the technical contacts listed below or the appropriate Office contact

Nuclear Reactor Regulation (NRR) project manager. of

Driai- b. (Grimes, Brian K. Grimes, Acting Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: David Skeen, NRR

(301) 415-1174 E-mail: dls~nrc.gov

Kamalakar Naidu, NRR

(301) 415-2980

E-mail: krn@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

DOCUMENT NAME: S:\DRPM SEC\96-46.IN

• See previous concurrence

OFC PECB:DRPM PSIB:DISP C/PSIB:DISP C/PECB:DRPM

NAME D. Skeen* K. Naidu* R. Gallo* A. Chaffee*

DATE . 8L0 2 691 8/05/96 8/05/96 8/05/96 T

1 - .' X - -

OFC

NAME [itZI

DATE 8/f/96 OFFICIAL RECORD COPY]

Ka'

. - r 'it IN 96- August , 1996 This information notice requires no specific action or written response. If

you have any questions about the information in this notice, please contact

one of the technical contacts listed below or the appropriate Office of

Nuclear Reactor Regulation (NRR) project manager.

Brian K. Grimes, Acting Director

Division of Reactor Program Management

Office of Nuclear Reactor Regulation

Technical contacts: David Skeen, NRR

(301) 415-1174 E-mail: dls@nrc.gov

Kamalakar Naidu, NRR

(301) 415-2980

E-mail: krn@nrc.gov

Attachment: List of Recently Issued NRC Information Notices

OFC lPECBJ

DRW PSIB:DIAP lC/PIB:a S PC]PM

NAME D. Ske K. Nai dtA *AChaffee

R.

DATE_ 8/2J96 8/5 /96 8/S /96 8/VK796 lOFC D/DRPM

NAME B. Grimes

DATE 8/ /96

[OFFICIAL RECORD COPY]

DOCUMENT NAME: G:\DLS\IN96-XX.ZNC