ENS 40783
ENS Event | |
|---|---|
04:00 May 28, 2004 | |
| Title | Part 21 Notification - Valve Actuator Switch Mechanisms |
| Event Description | Basic Component Affected
Rotork NA1 switch mechanism assemblies manufactured between 1978 (post 78 build) and November 2001 supplied either as a spares item or fitted in an NA1 type Electric Valve Actuator. Customers supplied with potentially affected actuators manufactured between January 1998 and November 2001, were previously notified individually of this condition and may have completed the risk assessment and corrective action detailed below. This report extends the affected time frame, potentially affecting actuators not identified on the original notifications. Rotork NA4, NA5, NA1E and NAE5 type Electric Valve Actuators are not affected. Nature of the Defect and Associated Safety Hazard It has recently been identified that the molded (PPS) components within the switch mechanism assembly have a low level of crystallinity and it cannot be confirmed that they are to the same specification as those originally tested and qualified at Wyle in 1978 (refer test report 43979-1 Rev A). Effect on Functionality The report provides a detailed explanation of the effect on function depending on the valve position and open/close action. NA4 and NAS type Electric Valve Actuators have a maximum ambient temperature rating of 70 deg C (160 deg F) and are not affected. NA1 type Electric Valve Actuators have the same ambient temperature rating but can be subject to a loss of coolant accident (LOCA). The condition reported will only affect Valve Actuators in plant locations where: 1) the LOCA and Operational temperature specifications, as defined in the Design Basis Document for each facility and location, could result in the switch mechanism components exceeding 80 deg C (176 deg F) and 2) The switch mechanism fitted was manufactured between 1978 and November 2001 and 3) The actuator is exposed to the two conditions outlined in section 2.0 of the report.
A revision to this report changes the Rotork model number from NAE5 to NA5E. Notified R1DO (Jenison), R2DO (Fredrickson), R3DO (Lanksbury), R4DO (Sanborn), NMSS Part 21 Coordinator (Torres) and NRR Part 21 Coordinator (Hodge) via fax. |
| Where | |
|---|---|
| Rotork Controls Inc Rochester, New York (NRC Region 1) | |
| Organization: | Rotork Controls Inc |
| Reporting | |
| 10 CFR 21.21 | |
| Time - Person (Reporting Time:+11.85 h0.494 days <br />0.0705 weeks <br />0.0162 months <br />) | |
| Opened: | Karen Black 15:51 May 28, 2004 |
| NRC Officer: | Mike Ripley |
| Last Updated: | Jun 3, 2004 |
| 40783 - NRC Website | |
Rotork Controls Inc with 10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation | |
WEEKMONTHYEARENS 407832004-05-28T04:00:00028 May 2004 04:00:00
[Table view]10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation Part 21 Notification - Valve Actuator Switch Mechanisms 2004-05-28T04:00:00 | |