ENS 48998
ENS Event | |
|---|---|
04:00 May 3, 2013 | |
| Title | Part 21 Report - Insufficient Process Control on Pump Impeller |
| Event Description | The following is a summary of information received via fax:
In January 2013, Curtiss-Wright Electro Mechanical Corporation completed final testing on AP1000 Reactor Coolant Pump (RCP) Serial Number 9, part number 6D70795G05, Revision 8, which contained a sand cast impeller (S/N 3021) cast by Wollaston Alloys of Braintree, MA. When it was disassembled for inspection it was discovered that a piece of an impeller blade approximately 3 inches by 2 1/2 inches had separated from the main impeller casting. The separated piece was the leading edge of one blade, and it was subsequently recovered intact from the pump test loop. This incident was investigated as a significant condition adverse to quality with the potential to create a substantial safety hazard; but, was deemed not a reportable incident since all cast impellers were either: 1) in CW-EMD control, or 2) exported to customers in the People's Republic of China. Our customers (Westinghouse Electric Company and the Chinese customers and regulatory authorities) were kept informed as the investigation progressed and root cause was identified. The physical cause of the failure is most likely due to a flaw present in both the cast material and weld overlay applied to the impeller blade. The original flaw was most likely a consequence of tensile overload failure due to cooling stresses introduced by the welding process. Subsequent weld repairs were insufficient in remediating the original flaw, which went undetected by NDT methods. Ultimately, AP1000 RCP Serial Number 3021 failed by high cycle fatigue followed by ductile failure. As a result of the above investigation, CW-EMD is concerned that the identified lack of process control at Wollaston Alloys, Inc., could result in other significant conditions adverse to quality with the potential to create a substantial safety hazard. Because of the nature of the issue, CW-EMD is unable to complete a full extent of condition investigation, and is reporting this issue to the Commission to ensure full awareness within the industry. Name and address of the individual or individuals informing the Commission: James A. Drake, General Manager Curtiss-Wright Electro-Mechanical Corporation 1000 Wright Way Cheswick, Pa 15024
Subject: Report of Potential Substantial Safety Hazard in accordance with Title 10 Code of Federal Regulations, Part 21. Wollaston Alloys is submitting this interim report as a result of product concerns discovered by Curtiss Wright EMD during the investigation of an impeller blade failure occurring during testing as noted in Curtiss Wright EMD's notification to the NRC dated May 3, 2013. Wollaston is requesting an additional 30 days to identify any current or previous orders where 10 CFR 21 is invoked and to determine if there is evidence that a condition exists that could create a substantial safety hazard. Notified R1DO (Schroeder), R2DO (Bartley), R3DO (Riemer), R4DO (Walker), and Part 21 Reactors via email.
Subject: Report of Potential Substantial Safety Hazard in accordance with Title 10 Code of Federal Regulations, Part 21. Wollaston Alloys, Inc. is submitting this report as an update to the interim report submitted on May 17, 2013 resulting from product concerns identified by Curtiss Wright EMD during the investigation of an impeller blade failure as noted in Curtiss Wright EMD's notification to the Nuclear Regulatory Commission (NRC), dated May 3, 2013. This investigation did not include the Curtiss Wright impeller failure since it is not considered a reportable incident, but addresses the identified concerns with regards to other products supplied to domestic users. The previously submitted interim report requested an additional 30 days to identify basic components supplied under the requirements of 10 CFR Part 21 and to determine if there is evidence that a defect or failure to comply exists. Name and address of the individual or individuals informing the Commission: Stephen M. Grief, Quality Manager Wollaston Alloys, Inc. 205 Wood Road Braintree, MA 02184 The complete report has been summarized as follows: Wollaston Alloys, Inc. determined the cases in which Wollaston Alloys, Inc. supplied components to which the requirements of 10 CFR Part 21 applied. After a review of all records pertaining to those purchase orders, Wollaston Alloys, Inc. found no evidence of a defect or failure to comply. Notified R1DO (Rogge), R2DO (Ehrhardt), R3DO (Daley), R4DO (Walker), and Part 21 Reactors via email. |
| Where | |
|---|---|
| Wollaston Alloys, Inc. Cheswick, Pennsylvania (NRC Region 1) | |
| Organization: | Curtiss Wright Flow Control Co. |
| Reporting | |
| Emergency class: | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+6.83 h0.285 days <br />0.0407 weeks <br />0.00936 months <br />) | |
| Opened: | James Drake 10:50 May 3, 2013 |
| NRC Officer: | Pete Snyder |
| Last Updated: | Jun 17, 2013 |
| 48998 - NRC Website | |
Wollaston Alloys, Inc. with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 489982013-05-03T04:00:0003 May 2013 04:00:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 Report - Insufficient Process Control on Pump Impeller 2013-05-03T04:00:00 | |