Semantic search
| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 49904 | 11 January 2014 04:00:00 | 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component | Part 21 - Ap-1000 Solenoid Operated Valves Leakage | The following was excerpted from a fax received from Valcor Engineering Corporation: Background: Valcor was chosen by WEC (Westinghouse Electric Corporation) as a supplier to the AP-1000 for the ASME Section Ill Class 1, 2 and 3 Solenoid Operated Valves. As part of the specification requirements Valcor is required to perform qualification testing in accordance with the requirements of IEEE-323-1974, IEEE-344-1987 and IEEE-382-1996. Discovery: On Saturday January 11th, 2014, Valcor's lab technician discovered that the hard faced seat of an AP-1000 Solenoid Operated qualification valve had a crack through the thickness of the valve seat to the outlet port that caused the valve to leak in the closed position beyond its Technical Specification requirement (WEC Specification APP-PV13-ZOD-101). The subject valve had undergone heat rise testing to determine actuator temperatures during its specified design basis conditions. As part of the qualification process (IEEE-323) and in accordance with the test procedure the subject valve is given a factory acceptance test (FAT) at each stage of the qualification program. The valve design is unique to the model (V526-5631-36/40) in that the dimensional constrain resulted in a web thickness of the hard faced seat that is thinner than our standard historical valve designs. A total of eight (8) valves of this configuration (four (4) for Valve Model Number V525-5631-36 and four (4) for Model number V526-5631-40) have been delivered to Westinghouse for installation in the Sanmen and Haiyang nuclear power plants located in the People's Republic of China. Neither of these plants have loaded fuel or are operational. The investigation, failure analyses, and stress analyses completed to-date have not provided a firm conclusion of the root cause of the crack. Westinghouse, the purchaser who imposed 10CFR21 on the procurement document of the valve models identified in question, has been informed of the condition and current status of investigation. Submitted by Jimmy Shieh Quality Assurance Director.
Subject: An update to Interim Report initially filed on 3/12/14, revised 3/13/14 Reference: SKA23651 previously submitted Investigation activities since the Interim Report: Computer Flow and Thermal Analysis conducted from March to April 2014. Finite Element Stress Analysis rerun using Computer Flow and Thermal Analysis in April 2014. Both analysis above suggest that the design is adequate and that stress induced by rapid temperature rise would not cause the seat to crack. With Westinghouse assistance and permission (two) 2 production valves were disassembled and NDE (Visual, LP, radiographic, and Eddy current) of body seat area performed during May. The examinations did not identify any defect in the valve seat area. Contrary to all stress/thermal analysis, cracking of valve seat was reproduced early June when one of the above mentioned bodies was subjected to the same thermal shock condition that caused the initial observed cracking. The second valve was tested at the same pressure and end temperature without the thermal shock. The valve seat remained intact without cracking. Westinghouse has been supporting the Part 21 investigation that Valcor is leading. Westinghouse has reviewed all metallurgy, CFD, FEA, NDE, heat rise laboratory and other data Valcor collected during our thorough investigation. All of this information is currently being evaluated by Westinghouse. At this time, the only outstanding issue is for Westinghouse to review all AP1000 transient conditions that are applicable to PV13 solenoid valves. Westinghouse anticipates having the preliminary transient research completed imminently and estimates to take until Nov. 30, 2014 to have all calculations and transient research validated. As stated in the original notification, the condition does not affect any operating plant. Affected valves are limited to overseas construction, none have been installed to date. Notified R2DO (Hopper) and NRR Part 21 Group via email.
Westinghouse has informed Valcor that none of the affected valves have been installed and they are quarantined from accidental installation. Valcor therefore is not required to pursue 10CFR21 reporting further and we (Valcor) consider the report closed. Notified R2DO (Seymour) and NRR Part 21 Group via email. | ||
| ENS 50799 | 9 February 2015 05:00:00 | 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component | Part 21 Report - Possible Assembly Error in Solenoid Valve | (The licensee) has discovered a possible assembly error that may result in compromising the capability to isolate the solenoid housing internals from a LOCA environment on some of our solenoid valve models that use grafoil packing for sealing the NEMA 4 enclosure. We are in the process of identifying the valve models affected and will notify all customers affected. Description of Defect/Non-Compliance: As noted on MRR997W the packing ring which seals the solenoid on valve model V526-5631-36 used in Qualification and Production were not matched to the procedure invoked on valve drawing. | ||
| ENS 52407 | 5 December 2016 05:00:00 | 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | Part 21 - Non-Conforming Cover Machining on Solenoid Valve | The following is a synopsis of the Part 21 report that was received via fax: Cover Machining is installed on upper section of Solenoid Valve and it allows for the electrical connection to the valve solenoid and protects inside wiring of the solenoid from environmental condition. Cover machining part number V52636-567 has 0.190 radius (Drawing V52620-50 Zone D3) which was machined too deep removing material from surface needed for proper O-ring seal. The lack of material exposes part of the sealing O-ring which could diminish the O-ring sealing capability. With O-ring sealing capability diminished, Valcor cannot ensure that valves with Cover Machining Installed on Solenoid Assembly will perform its safety function during all postulated events. This item has historically been manufactured by machining a casting. For the lot involved, castings were not available. Authorization was given to manufacture the Cover directly from suitable bar stock. To accomplish this, Valcor's vendor used the casting drawing and casting machining drawing to manufacture the finished machined part. The combination of these two drawings had insufficient control on the corner radius, resulting in this nonconformance. All defective covers in stock have been quarantined and a nonconformance report has been generated. Lack of location controlling dimension on the Cover Machining drawing for 0.190 radius was discovered to be the root cause of the defect. Valcor has created and released a new engineering drawing that properly controls the location of 0.190 radius. This action has been completed as of 11/22/2016. Engineering Manager-Nuclear was responsible to this action. Valcor is in a process of notifying all affected customers. Customers: Ameren, Valve Part Number V526-6000-16 (Stock# 7731643), S/N 9, QTY 1, Location Ameren Missouri - Callaway Bruce Power (BPC), Valve Part Number V526-6000-20 (Cat ID 142129), S/N 28-36, QTY 9, Bruce NGS Note: All 9 valves supplied to BPC have been returned to Valcor for nameplate correction and are accounted for. If you have any questions or addition information is needed regarding this matter, please contact Fran Lucano at 973-467-8400. | ||
| ENS 55999 | 19 May 2022 04:00:00 | 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect 10 CFR 21.21(a)(2), Interim Report for Comply or Defect in Component | Part 21 Report - Potential Premature Failures of Valcor Coil Shell Assemblies | The following is a synopsis of information received via facsimile: Valcor Engineering Corporation (VEC) was notified via a letter dated 5/19/2022 that Catawba Nuclear Station (CNS) discovered two failed Coil Shell Assemblies, part number V52653-6040-7, which were removed from V70900-39-3-1 Solenoid Valves and returned to VEC for evaluation. VEC has not concluded this is a reportable condition in accordance with 10 CFR 21.22(d) and requires additional time to complete testing and evaluation. VEC is submitting this 60-day Interim Report Notification per 10 CFR 21.21(a)(2). VEC will complete the evaluation and provide a determination of reportability in accordance with Part 21 no later than 09/12/2022. Currently, Catawba Nuclear Station is the only affected facility. For additional information, please contact Mike Swirad, Valcor Engineering Quality Assurance Director (973-467-8400 x 7223)
The following is a synopsis of information received via facsimile: VEC is providing final notification with regard to defects in coil shell assemblies (part number V52653-6040-7) per 10CFR Part 21.21(d)(4). The root cause of failure of this part was determined to be an internal short in the coil shell assembly. In addition to Catawba, licensees affected are: Brunswick, Callaway Energy Center, Oconee, Braidwood, and Fitzpatrick. Root cause of the failed component is inconsistency in the coil assembly manufacturing process. VEC initiated internal and supplier corrective actions and all coil shell assemblies have been quarantined and VEC supplier was notified. All existing coil assemblies in stock will be reworked to conform to VEC drawings. Completion of rework expected within 60 days. VEC is in the process of notifying all affected customers. Defect can not be visually or electrically identified. All coil assemblies that perform safety related function must be returned to VEC for evaluation/replacement. For additional information, please contact Mike Swirad, Valcor Engineering Quality Assurance Director (973-467-8400 x 7223) Notified R1DO (Young), R2DO (Miller), R3DO (Hanna), R4DO (Drake) and via email: Part 21 Reactors. | ||
| ENS 56907 | 23 October 2023 06:00:00 | 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | Part 21 Report - Defect in Valcor Solenoid Valves | The following is a synopsis of information received via facsimile: Valcor Engineering Corporation (VEC) identified a defect with Valcor solenoid valves with part number V52600-5890-1 on October 23, 2023. The defect identified is that stroke matching of internal components was not performed in accordance with internal procedures causing valve flow coefficient (Cv) to be only approximately 50 percent of the minimum required Cv of 2. Substantial safety hazard could be created if the flow rate through the solenoid valve exceeded a certain threshold. VEC has identified two of these solenoid valves at LaSalle County Nuclear Generating Station (LaSalle) with serial numbers 33 and 34. For corrective actions, VEC repaired and returned the valve with serial number 34 to LaSalle. To prevent recurrence, VEC intends to improve the training program for production personnel and, if needed, review and revise the stroke matching procedure including enhancing quality assurance oversight of that process. VEC estimates it will take 30 days to complete corrective actions. Currently, LaSalle is the only known affected facility. Valcor is in the process of identifying and notifying affected customers. For additional information, please contact Mike Swirad, Valcor Engineering Quality Assurance Director (973-467-8400 x 7223), email: mikeswirad@valcor.com |