ML20094F631

Interim Deficiency Rept Re Limitorque Motor Operators. Initially Reported on 840525.Limitorque Improved Design by Replacing Fiber Shims W/Metal Shims.Next Rept Will Be Submitted by 841031

ML20094F631
Person / Time
Site:	Seabrook
Issue date:	07/30/1984
From:	Devincentis J PUBLIC SERVICE CO. OF NEW HAMPSHIRE, YANKEE ATOMIC ELECTRIC CO.
To:	Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
SBN-702, NUDOCS 8408100136
Download: ML20094F631 (4)

Text

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PUEBLIC BERVICE 5"N ""

Companyof New Hempehre

.J.u. ome .

1671 Worcester Road Fromingham. Massachusetts 0i701 (617) - 872 - 8100 ,,

July 30, 1984 SBN- 702 T.F. Q2.2.2 United States Nuclear Regulatory Commission Region I 631 Park Avenue King of Prussia, PA 19406 Attention: Mr. Richard W. Starostecki, Director Division of Project and Resident Programs

References:

(a) Construction Permits CPPR-135 and CPPR-136, Docket Nos. 50-443 and 50-444 (b) PSNH Letter, dated May 25,1984, " Interim 10CFR50.55(e)

Report: Limitorque Motor Operators", J. DeVincentis to R. W. Starostecki

Subject:

Interim 10CFR50.55(e) Report: Limitorque Motor Operators

Dear Sir:

In Reference (b), we filed an interim 10CFR50.55(e) report regarding four potential deficiencies with Limitorque motor operators. We have determined that items 1 and 4 are reportable per 10CFR50.55(e), and that items 2 and 3 require further evaluation to determine their reportability.

Description of Deficiencies A description of the several Limitorque operator deficiencies is as follows:

Item 1 Loose Contact Screws on Contact Bridge of Torque Switch '

The improper operation of some motor operators was traced to loose contact screws on the contact bridge of the torque switch. These loose screws are apparently a result of either inadequately tightened screws or the relaxation of fiber shims under the contact bridge, which causes the screws to loosen. This problem appears to be limited to the torque switch type used in SMB-000 operators.

8408100136 840730 PDR ADOCK 05000443 S PDR /

eV a,

' Unitsd States Nuclear R2gulatory C mmissica July 30, 1984 Attention: Mr. Richard W. Starostecki, Director Page 2

, Item 2 Incorrect Spring Pack . . .

The improper operation of sixteen operators was determined to be a result of incorrectly supplied spring packs. These operators (all sequential serial numbers) were supplied under the same purchase order.

Item 3 Incorrect Limiter Plate on Torque Switch A number of operators were observed to have torque switch limiter plates which could allow torque switch settings greater than stated on the torque switch calibration sticker.

Item 4 Improper Lug Connections A number of operators were found to have various deficiencies concerning terminal lug connections. These include poor crimps, exposed wirestrands, and damaged wire insulation.

Safety Implications

Item 1 Loose contact screws, if lef t uncorrected, can lead to a loss I

of electrical continuity in the control circuit and -

subsequent to valve operator failure. This could prevent a safety-related valve from performing its safety function. 1 Items 2 & 3 We are continuing to investigate the cause and safety implications of these deficiencies.

Item 4 Poor crimps, exposed wirestrands, and damaged wire j insulation, if lef t uncorrected, can lead to valve operator. t failure. This could prevent a safety-related valve from performing ~ its safety function. 1 Corrective Action i

Item 1 Limitorque has informed us that they have received only one other report of loose contact screws during the 15 years that this torque switch design has been in use. To eliminate any possibility that the fiber shims used under the contact bridge are responsible for the loosening of the contact screws, Limitorque has implemented a' design improvement by replacing the fiber shims with metal shims on current produc tion. In accordance with Limitorque's latest j procedures, we have included the replacement of the fiber l

shims with metal shims, and the tightening of the contact

- screws into our test procedures to eliminate the possibility of any future problems.

Items 2 & 3 Corrective action, if any, to be determined af ter contact with vendors.

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oEITJ Utst03 Nucleo; R2gulct Attantient \

Mr. Richard W. Storastcckicry Ccamiccica

, Dirsctor July 30, 1984 Page 3 j Item 4 )

During our relubrication/verifi testing, lug connections and replaced or repaired to incation

, crimps, effort and startup and ,wi, ring are inspecte to determine reportabilityThe sure acceptable vendor response quality.receive or corrective action. pertaining to Items 2 and 3 to Region I by October 31 additional information from

, 1984 vendor.

We will submit an additiona obtain response of 10CFR50.55(e)(3).This letter is being filed p ursuant to the interim reportin g provisions Very truly yours, YANKEE ATOMIC ELECTRIC h

cc: J. DeVincentis Engineering Manager Atomic Safety and Licensing B

• Director, Office of Inspecti oard Service List Washington, DCU.S. Nuclear ssion Regulatory Commion and Enfe.s. m 20555 l

- '* William S. Jordan, III

. Diana Curran H rmon, Weics & Jordan '

20001 S Street N.W. Drentwood Board of Selectmen Suite 430 RED Dalton Road I washington, D.C. 20009 Brentwood, New Hampshire 03833 Roy P. Lessy, Jr., Esquire Office of the Executive Legal Director Edward F. Meany -

U.S. Nuclear Regulatory Commission Designated Representative of Washington, DC 20555 the Town of Rye 155 Washington Road Robert A. Backus, Esquire Rye, NH 03870 116 Lowell Street P.O. Box 516 Calvin A. Canney Mancehster, NH 03105 City Manager City Hall Philip Ahrens, Esquire 126 Daniel Street Assistant Attorney General Portsmouth, NH 03801 Department of the Attorney General Augusta ME 04333 Dana Bisbee, Esquire Assistant Attorney General Mr. John B. Tanzer Office of the Attorney General Designated Representative of 208 State House Annex the Town of Hampton Concord, NH 03301 5 Morningside Drive Hampton, NH 03842 Anne Verge, Chairperson Board of Selectmen Roberta C. Fevear Town Hall Designated Representative of South Hampton, NH 03S42 the Town of Hampton Falls Drinkwater Road Patrick J. McKeon Hampton Falls, NN 03844 Selectmen's Office 10 Central Road Mrs. Sandra Cavutis Rye, NH 03670 Designated Representative of the Town of Kensington RFD 1 Carole F. Kagan, Esq.

East Kingston, NH 03827 Atomic Safety and Licensing Board Fanel U.S. Nuclear Regulatory Commission Jo Ann Shotwell, Esquire ' **

Assistant Attorney General Mr. Angie Machiros Environroental Protection Bureau Chairman of the Board of Selectmen Department of the Attorney General Town of Newbury One Ashburton Place, 19th Floor Newbury, MA 01950 Boston, MA 02108 Town Manager's Office Senator Gordon J. Humphrey Town Hall - Friend Street U.S. Senate Amesbury, Ma. 01913 Washington, DC 20510 (Attn: Tom Burack) Senator Gordon J. Humphrey 1 Pillsbury Street Diana P. Randall Concord, NH 03301 70 Collins Street (Attn: Herb Boynton)

SEabrook, NH 03874 Richard E. Sullivan, Mayor Donald E. Chick City Hall Town Manager Newburyport, MA 01950 Town of Exeter ,

10 Tront Street 7*

Exeter, NH 03833 i

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