ENS 52867
ENS Event | |
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20:46 Jul 14, 2017 | |
Title | Part 21 Notification - Eaton/Cutler Hammer A200 Series Starter |
Event Description | The following information was received by the licensee via email:
Pursuant to 10 CFR 21, this is a non-emergency notification by Susquehanna Nuclear, LLC concerning a defect in an Eaton/Cutler Hammer A200 series starter that failed while in service at Susquehanna Steam Electric Station. The failed starter was manufactured by Eaton Corporation in 2014 and purchased by Susquehanna from AZZ/NLI as part of an MCC bucket assembly. The starter failed with its contacts stuck in the energized state when it was de-energized. A failure analysis identified the contactor sticking to be due to the pole faces of the coil laminations and those of the armature laminations adhering to one another at normal operating temperatures. There was residue/material on the pole faces which closely matched Polydimethylsiloxane (PDMS) and silicone grease. One of the characteristics of PDMS is that at cooler temperatures it is more of a solid consistency, and at higher temperatures it becomes more viscous and tacky. A previous Part 21 report submitted by Curtiss-Wright QualTech NP (Event Notification 51611) in December 2015 provided notification of Eaton/Cutler Hammer A200 series starters failures due to silicon based mold release that remained on the molded parts and would come between the moving (magnet) and fixed armatures. The Part 21 stated that when heated for extended period of time, the material would become sticky causing anywhere from a minor delay in opening to a frozen closed condition. Eaton/Cutler Hammer determined that the silicone mold release was first introduced into the manufacturing facility in May 2008 and used periodically until October 2012. According to Eaton/Cutler Hammer, any starters manufactured after January 1, 2013 should be silicon mold release free. Following the failure of the 2014 starter at Susquehanna, Eaton Corporation performed an investigation and reconfirmed that silicon mold release was banned from molding production in October 2012 and has not been used since that time. Eaton concluded that the contamination does not appear to be systemic, but rather random and intermittent and that the contamination was most likely introduced either by operators and assemblers on the manufacturing lines, or by others who disassemble and inspect the product after shipment from their plant. Susquehanna does not take the components apart during receipt for testing or visual inspection. Eaton concluded that there is no evidence that the issue is systemic and considers it a random event. Susquehanna has evaluated the condition and has concluded that the condition could create a substantial safety hazard. The licensee notified the NRC Resident Inspector. |
Where | |
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Eaton/Cutler Hammer Berwick, Pennsylvania (NRC Region 1) | |
Organization: | Susquehanna Nuclear Llc |
Reporting | |
10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
Time - Person (Reporting Time:+157.9 h6.579 days <br />0.94 weeks <br />0.216 months <br />) | |
Opened: | Jason Jennings 10:40 Jul 21, 2017 |
NRC Officer: | Vince Klco |
Last Updated: | Jul 21, 2017 |
52867 - NRC Website | |
Eaton/Cutler Hammer with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 528672017-07-14T20:46:00014 July 2017 20:46:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 Notification - Eaton/Cutler Hammer A200 Series Starter 2017-07-14T20:46:00 | |