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ACCESSION #: 9610310065 NOTE: This text document was processed from a scanned version or an electronic submittal and has been processed as received. Some tables, figures, strikeouts, redlines, and enclosures may not have been included with this submittal, or have been omitted due to ASCII text conversion limitations. In order to view this document in its entirety, you may wish to use the NUDOCS microfiche in addition to the electronic text. AV AUTOMATIC VALVE 41144 Vincent Court Novi MI USA 48375-1924 Telephone 810-474-6700 Facsimile 810-474-6732 World Class Air Valves and Controls OCTOBER 28, 1996 SUBJECT: 10CFR21 NOTIFICATION OF POTENTIAL DEFECT On 09-02-96 Jim Wethington, of Commonwealth Edison-Quad Cities NPS, notified Automatic Valve that a Main Steam Isolation Valve (MSIV) EPN 1-0203-1D had failed to close in the 3-5 seconds required by their technical specifications. The solenoid valves associated with the MSIV had recently been replaced by Quad Cities personnel. Following replacement, the MSIV stroked property under cold conditions (reactor shutdown and solenoid valves de-energized prior to testing). The concern was identified while re-timing the MSIV during plant start-up. After the solenoids had remained energized for several hours the MSIV would not close within the required 3-5 seconds. On 09-03-96 Todd Hutchins of Automatic Valve inspected the solenoid at the Quad Cities facility and determined that the 6910-0x0 solenoid plunger was 1.322-1.327" in length. The correct specified length is 1.287-1.295". The probable cause of the incorrect length appeared to be a missed machining operation at time of manufacture. A solenoid plunger of this length restricts the exhaust port in the plunger stem. This potentially can prevent any equipment operated by the solenoid from operating within its intended time requirement. On 09-04-96 Todd Hutchins and Jim Wethington discussed the non- conformance and initial corrective action with Keith Walton and Laura Collins of the Nuclear Regulatory Commission located at the Quad Cities facility. Automatic Valve verified that all of the 6910-0x0 solenoid plungers currently in their stock were the correct length and added a specific inspection requirement for all future plungers. To prevent any additional valves from being rebuilt with potentially long plungers Automatic Valve requested all customers who had received kits containing the 6910-0x0 solenoid plunger in the last two years to verify the plunger length. It had been Automatic Valve's experience that kits supplied previous to the two year cutoff were already installed in operating valves and could not immediately be measured. The defective solenoid from Quad Cities was returned on 09-27-96 to Automatic Valve for additional testing and root cause determination. Frank Lentin of Commonwealth Page 2 October 28, 1996 Subject: 10CFR21 Notification of Potential Defect Edison notified Automatic Valve that a 10CFR21 review had been initiated and that a decision on potential reportability was required by 11-04-96. On 10-17-96 preliminary test data indicated that field detection of the non-conforming plunger was possible with a dimensional inspection (requiring the solenoid to be disassembled) or time testing the product after the solenoid had reached it's stabilized temperature (but not during its initial cold state). Since the missed machining operation on the plunger was an omission in the machining process, the problem is not lot specific. Potentially all solenoid valves manufactured since 02-03-70 (utilizing the 10 watt #6910- 0x0 solenoid) with the model numbers prefixed A, B, C, K, or U are affected. If you are unsure as to whether this affects you, please submit questionable part numbers to Automatic Valve for verification. There have been no reported non-conforming plungers shipped in the previous 26 years. All known customers (list attached) were verbally notified of the potential problem, verbally notified of the recommended corrective action, given an assurance that a formal 10CFR21 decision would-be made by 11-04-96 and that they would receive a copy. The formal corrective action report (attached) was completed on 10-28-96 and outlines the problem, root cause, corrective action, implementation, and preventative action. This letter intends to fulfill Automatic Valve's obligation under 10CFR21 and is being sent with all attachments to all known customers who have purchased products containing the potentially long plunger and who have imposed 10CFR21 in their purchase order. Should you have any additional questions, please feel free to contact me. Very truly yours, AUTOMATIC VALVE CORPORATION Todd Hutchins President TJH/cb 10cfr2[Trademark]1.doc AUTOMATIC VALVE CORRECTIVE ACTION 10/28/96 9622A 1. Team: Jim Wethington, Quad Cities NPS, tel:309.654.2241x2190 Todd Hutchins, Automatic Valve, tel:810.474.6700 2. Problem: On 09-02-96 MSIV #1-0203-1D would not fast close within the 3-5 second technical specification when the solenoids had been energized for a minimum of two hours at a minimum of 90'F ambient. 3. Containment: Air pack ser# D53325 was removed from MSIV #1-0203-1D for inspection by Automatic Valve personnel at Quad Cities. Air pack ser# D53332 was rebuilt for installation on MSIV #1-0203-1D on 09-04-96. 4. Cause: One plunger from solenoid 6910-0x0 missed the machining operation after the viton insert was pressed in. 5. Corrective action: 5.1 For products in the field: Verify the plunger length to be 1.287-1.295" or verify when de-energized that the application speed meets technical specifications after the solenoid has been energized for a minimum of two hours at a minimum of 90'F ambient. 5.2 For products at Automatic Valve: Verify flow/response time and/or verify plunger length. 6. Verification: 6.1 Verified that the non-conforming plunger was fully assembled but had missed the machining operation (based on x-rays and photos). 6.2 Verified that the non-conforming plunger when energized for minimum of two hours at a minimum of 90'F ambient would cause significant delay in de-energize flow time (test report PV-UTL-46 attached). 6.3 Verified that the non-conforming plunger could be identified by a flow/response time test. 7. Implementation: 7.1 Plants should verify that the plunger length is 1.287- 1.295" or verify when de-energized that the application speed meets technical specifications after the solenoid has been energized for a minimum of two hours at a minimum of 90'F ambient. 7.2 Automatic Valve added plunger length as a critical 'to be inspected' dimension on the inspection print (print #6910- 0X0 attached). Current stock at Automatic Valve was re- inspected and found all to be within tolerance. Service kits sold to customers in 1995 and 1996 still in stock were re-inspected and found all to be within tolerance (contacts attached). 1 AUTOMATIC VALVE CORRECTIVE ACTION 10/28/96 9622A 7.3 Automatic Valve verified flow/response time and/or plunger length on all shipments since 09-04-96. 7.4 On 10-28-96 Automatic Valve notified in writing all known customers who had purchased products containing the potentially long plunger and who had imposed 10CFR21 in their purchase order. 8. Prevention: 8.1 Plants should add plunger dimensions to field rebuild instructions (example attached). 8.2 Automatic Valve added critical solenoid dimensions to engineering 'critical characteristics' procedure. 8.3 Automatic Valve added flow/response time requirements to final test procedure. 9. Verification: Monitor testing and field feedback data. 2 AUTOMATIC VALVE LOCN: I:\DSS\DOCUMENT\PVUTL46 DATE: 10-26-1996 TEST NUMBER: PV-UTL-46 PURPOSE: To determine the effects of ambient temperatures on the energize and de- energize times of solenoid 6910-0X0, with: o Non-conforming 6910-001 solenoid plunger - length of 1.322 - 1.327 - as returned from Commonwealth Edison. o Conforming 6910-001 solenoid plunger - length of 1.287 - 1.295 TEST PROCEDURE: 1. Run all tests at 80 psig using filtered non-lubricated air. 2. Attach solenoid manifold with non-conforming plunger to test plate AX-402. 3. With the manifold at ambient temperature, record the following temperatures - also refer to figure 1. 3.1. Ta-Ambient temperature 3.2. T1 - Temperature of solenoid adapter nut. 3.3. T2- Temperature of solenoid coil housing. 3.4. T3 - Temperature of solenoid manifold block. (Note: Physically mark the locations where temperature readings are taken and take all subsequent temperature readings at the same locations.) 4. Determine flow and exhaust response times taking 3 to 5 readings waiting a minimum of 10 minutes between readings to allow system to stabalize. 4.1 During each reading record temperatures at locations designated in paragraph 3. 5. With the manifold at ambient temperature, energize the solenoid for a minimum of 2 hours. 5.1. Record temperatures T1 through T3 per paragraph 3. 5.2 Determine flow and exhaust response times and record temperatures per paragraphs 4 through 4.1. 6. Disconnect air inlet line, remove the pressure transducer and place the manifold, test plate, and load chamber in an oven and heat to 90 degrees F for a minimum of 1/2 hour with the solenoid energized. 6.1. Measures temperatures T1 through T3 per paragraph 3 prior to running response tests. 6.2 Determine flow and exhaust times and record temperatures per paragraphs 4 through 4.1. 6.2.1 During the wait between readings, reinsert the manifold in the oven to re-establish temperatures. 7. Repeat paragraph 6 through 6.2 at oven temperatures of 90 degrees F, 100 degrees F, 125 degrees F, and 150 degrees F. 8. Repeat paragraphs 2 through 7 with conforming solenoid plunger. TEST EQUIPMENT: Number Description Calibration Date APG-2 0 to 60 160 PSIG pressure gage 10-02-1996 NIC-3091 Osciloscope 06-10-1996 7199 Thermocouple thermometer 10-04-1996 TTT-1100-550 Thermometer 11-07-1995 SPT-667388 Pressure transducer 06-24-1996 AUTOMATIC VALVE LOCN: I:\DSS\DOCUMENT\PVUTL46 DATE: 10-26-1996 Table "TEST RESULTS (AVERAGES" omitted. ANALYSIS/CONCLUSIONS: 1. Ambient temperature fluctuations have little effect on either the energized or de-energized times with the conforming plunger installed. 2. Ambient temperature fluctuations have only a slight effect on the energized times with the non-conforming plunger installed. 3. Ambient temperature fluctuations have a significant effect on de- energized times with the non-conforming plunger As the data shows, at an ambient temperature of 90 degrees F the unit became, for practical purposes, non functional. The 'quickest' exhaust time with the surface of the body at 93.4 degrees F was 54 seconds compared to 0.145 for the manifold with the conforming plunger. 4. At a minimum ambient temperature of 90 degrees F and with the solenoid coil energized for a minimum of 2 hours, the delay in the de-energized time would be easily detectable. As the ambient temperature increases, the delay becomes more and more noticable. Conducted by : Brian Bielat Title: Engineer Date: 10-25-1996 Analized by: Title: VP Eng/Mfg Date: 10-26-1996 Approved by: Title: VP Eng/Mfg Date: Figure "AUTOMATIC VALVE SOLENOID #6910-0X0 10/28/96" omitted. AUTOMATIC VALVE SHIPPEDKITSWITH6910-0X0 10/25/96 Table omitted. Page 1 QCEMS 0250-16 UNIT 1 (2) REVISION 7 Figure 4 "Ref: GE SIL 505, MSIV SOLENOID MANIFOLD" omitted. GENERAL INFORMATION or OTHER EVENT NUMBER: 31229 LICENSEE : AUTOMATIC VALVE NOTIFICATION DATE: 10/28/96 CITY: NOVI REGION: 3 NOTIFICATION TIME: 12:13 [ET] COUNTY: STATE: MI EVENT DATE: 10/28/96 LICENSE #: AGREEMENT: N EVENT TIME: 00:00[EST] DOCKET: LAST UPDATE DATE: 10/28/96 NOTIFICATIONS NRC NOTIFIED BY: HUTCHINS HQ OPS OFFICER: CHAUNCEY GOULD VERN HODGE EMERGENCY CLASS: NOT APPLICABLE 10 CFR SECTION: WINF INFORMATION ONLY CCCC 21.21 UNSPECIFIED PARAGRAPH EVENT TEXT AUTOMATIC VALVE WAS NOTIFIED BY COMMONWEALTH EDISON-QUAD CITIES THAT A MAIN STEAM ISOLATION VALVED FAILED TO CLOSE WITHIN THE 3-5 SECONDS REQUIRED BY THEIR TS. FURTHER INSPECTION BY AUTOMATIC VALVE PERSONNEL DETERMINED THAT THE "6910-0X0" SOLENOID PLUNGER WAS TOO LONG. THE PROBABLE CAUSE FOR THE INCORRECT LENGTH APPEARED TO BE A MISSED MACHINING OPERATION AT TIME OF MANUFACTURE. AUTOMATIC VALVE VERIFIED THAT ALL SOLENOID PLUNGERS OF THIS TYPE IN THEIR STOCK WERE THE CORRECT LENGTH AND ADDED A SPECIFIC INSPECTION REQUIREMENT FOR ALL FUTURE PLUNGERS. AUTOMATIC VALVE REQUESTED THAT ALL CUSTOMERS WHO RECEIVED KITS WITHIN THE LAST 2 YEARS CONTAINING THIS TYPE PLUNGER TO VERIFY THE PLUNGER LENGTH. AUTOMATIC VALVE 10CFR21NOTIFICATION 10/25/96 Table omitted. Page 1 *** END OF DOCUMENT ***