ML20207G953
| ML20207G953 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 07/14/1986 |
| From: | Swanson N NAMCO CONTROLS |
| To: | Zech G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| Shared Package | |
| ML20207G948 | List: |
| References | |
| REF-PT21-86 NUDOCS 8607230262 | |
| Download: ML20207G953 (2) | |
Text
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s Namco Conttis 7567 Tylu Boulevnd Mentor, Ohio 44060 (216) 946-9900 g g g g gg e Telex 24-1566 seca,se nouung wse works derra July 14, 1986 Corrected Copy Mr. Gary Zech Chief - Vendor Program U.S. Nuclear Regulator Commission Washington, D.C.
20555
Subject:
Notification of a possible product defect as required by 10CFR21.
Namco part FEA188-30007 Contact Lever Assembly for Series EA180 Limit Switches
Dear Mr. Zech:
We have been advised by Stone & Webster Engineering Corporation that their inspectors at Niagara Mohawk's Nine Mile Point have foand cracks in plastic contact lever arms in 14 qualified Namco EA180 limit switches.
We have ob-tained samples of these parts from the plant, and examined them on July 11, 1986. (See a copy of our drawing enclosed.)
i Tne parts returned to us were taken from switches manufactured in 1979, accord-ing to the date code on the exterior of the switch housing. This is the first report of this condition that we have received from a field installation, and our records show that we have shipped over 40,000 EA180 switches in the 1
last 10 years.
Inasmuch as we do not know whether the cracked condition could lead to fracture and subsequent switch failure, we are proceeding as follows:
1.
Proposing to Niagara Mohawk that they replace cracked contact lever arma in all Category I safety-related limit switches with new lever arms, which we will provide.
2.
Initiating a test program of switches with cracked lever arms returned from Nine Mile Point to determine if the cracks even-tually cause switch failure, and if so, after how many normal operations.
3.
Reviewing the specified plastic materials and production pro-cesses involved with these lever arms, to insure that the con-dition does not recur.
8607230262 860714 PDR ADOCK 05000410 S
PDR AN ACMF CLFvFL AND COwuNv
/
e' NAMCO OONTRot S U. S. Nuclear Regulatory Commission July 14, 1986 Pending the outcome of our life testing in #2 above, we will advise the NRC and our utility customers what action we recommend be taken to insure that this problem is properly corrected, if corrective action is required.
i Verv truLy yours,
/
bMMr N. E. Swanson President NAMCO CONTROLS NES/kg Attach.
cc: E. L. Laskowski E. L. Roob C. E. Crocker, Stone & Webster Engrg. Corp.
Nine Mlle Pt. #2 P.O. Box 63 Lycoming, NY 13093 i
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