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Category:DEFICIENCY REPORTS (PER 10CFR50.55E & PART 21)
MONTHYEARML20125C7161992-12-0707 December 1992 Part 21 Rept Re Possibility for Malfunction of Declutching Mechanisms in SMB/SB-000 & SMB/SB/SBD-00 Actuators. Malfunction Only Occurs During Seismic Event.Balanced Levers May Be Purchased from Vendor.List of Affected Utils Encl ML20058P7841990-08-14014 August 1990 Part 21 Rept Re Misapplication of Fluorolube FS-5 Oil in Main Steam Line Pressure Gauges.All Four Indicators Replaced W/Spare Gauges Which Utilize High Temp Silicone Oil ML20154M1641988-04-26026 April 1988 Part 21 Rept Re Design Defect in Automatic Switch Co Tripoint SB12BMR/TL10A22 Pressure Switches.Surveillance Cycle Increased from Monthly to Semimonthly & Mfg to Assist in Determining Cause of Failure ML20214A1361987-05-12012 May 1987 Part 21 Rept Re Capacity of Thermal Compensating Accumulator Being Insufficient to Compensate for Thermal Expansions of Hydraulic Fluid During Full Ambient Temp Transient Required by Customer Specs.Interim & Permanent Mods Identified ML20210G9921985-08-13013 August 1985 Part 21 Rept Re Failure of Isolated Worm Shaft Gear When Certain Critical Speeds Combined W/Repetitive Transfer of Actuator Clutch Mechanism from Manual (Handwheel) to Motor Drive Mode.Two Possible Solutions Noted 1992-12-07
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217C1311999-10-0808 October 1999 Safety Evaluation Supporting Amend 153 to License DPR-3 ML20211J5111999-08-31031 August 1999 Rev 29 to Yankee Decommissioning QA Program ML20211J3361999-08-27027 August 1999 Safety Evaluation Supporting Amend 152 to License DPR-3 ML20209D5391999-06-22022 June 1999 Rev 29 to Yaec Decommissioning QA Program ML20207F9491999-03-0505 March 1999 Safety Evaluation Supporting Amend 151 to License DPR-3 ML20202H5871999-02-0303 February 1999 Safety Evaluation Supporting Amend 150 to License DPR-3 ML20154P9691998-10-16016 October 1998 Rev 28 to Yankee Atomic Electric Co Decommissioning QA Program ML20249A7901998-06-17017 June 1998 Safety Evaluation Supporting Amend 149 to License DPR-3 ML20216C4581998-02-27027 February 1998 Response to NRC Demand for Info (NRC OI Rept 1-95-050) ML20203L1931998-02-25025 February 1998 Duke Energy Corp,Duke Engineering & Svcs,Inc,Yankee Atomic Small Break LOCA Technical Review Rept ML20203L2451998-02-23023 February 1998 Assessment Rept of Engineering & Technical Work Process Utilized at De&S Bolton Ofc ML20203L1621998-02-18018 February 1998 Rept of Root Cause Assessment Review ML20203L2691998-02-16016 February 1998 Duke Engineering & Svcs Assessment Process Review Rept ML20199B4601998-01-20020 January 1998 Special Rept:On 980105,meteorological Monnitoring Instrumentation for Air Temp Delta T Inoperable for More than 7 Days.Caused by Breakdown in Wiring Between Junction Box at 199 Foot Level.Wiring Replaced ML20203J3001997-12-31031 December 1997 Ynps 1997 Annual Rept ML20217N0981997-08-21021 August 1997 LER 97-S02-00:on 970725,discovered Uncontrolled Safeguards Documents.Caused by Personnel Error.Matls Retrieved & Stored in Safeguards Repositories ML20210H0991997-08-0707 August 1997 LER 97-S01-00:on 970709,potential Compromise of Safeguards Info Occurred.Caused by Human error.Stand-alone Personal Computer & Printer Not Connected to Network,Have Been Located within Text Graphics Svc Dept ML20149K7781997-07-24024 July 1997 Special Rept:On 970520 & 0714,air Temp Delta T Channel Indicated Temp Difference Between Top & Bottom of Meteorological Tower.Caused by Reversed Input Wiring to Channel.Restored Air Temp Delta T Channel Operability ML20141E4671997-05-30030 May 1997 Rev 28 to Operational QA Program ML20135C8461996-12-31031 December 1996 Yankee Nuclear Power Station 1996 Annual Rept ML20132G6771996-12-20020 December 1996 Rev 27 to YOQAP-I-A, Operational QA Program ML20058N4771993-12-20020 December 1993 Rev 0.0 to Yankee Nuclear Power Station Decommissioning Plan ML20059K8491993-12-15015 December 1993 Clarifications to Pages 2,41,43 & 44 of 44 in Section I, Organization of YOQAP-I-A,Rev 24, Operational QA Program ML20059C5011993-10-29029 October 1993 Special Rept:On 931019,meteorological Instrumentation Channel for Delta T Declared Inoperable.Caused by Ceased Aspirator Motor Located at Top of Tower.Motor Replaced ML20056H1741993-06-10010 June 1993 Preliminary Assessment of Potential Human Exposures to Routine Tritium Emissions from Yankee Atomic Electric Co Nuclear Power Facility Located Near Rowe,Ma ML20237F1671993-02-19019 February 1993 Safety Evaluation Supporting Amend 147 to License DPR-3 ML20125C7161992-12-0707 December 1992 Part 21 Rept Re Possibility for Malfunction of Declutching Mechanisms in SMB/SB-000 & SMB/SB/SBD-00 Actuators. Malfunction Only Occurs During Seismic Event.Balanced Levers May Be Purchased from Vendor.List of Affected Utils Encl ML20198D2541992-05-13013 May 1992 Yankee Nuclear Power Station Certified Fuel Handler Recertification Program ML20198D2481992-05-13013 May 1992 Yankee Nuclear Power Station Certified Fuel Handler Initial Certification Program ML20062H1981990-11-30030 November 1990 Plant Specific Fast Neutron Exposure Evaluations for First 20 Operating Fuel Cycles of Yankee Rowe Reactor ML20058H2841990-11-0303 November 1990 Special Rept:On 901101,control Rod 24 Found Disconnected from Drive Shaft.Drive Shaft Latching Will Be Initiated ML20058F2201990-11-0202 November 1990 Safety Evaluation Accepting Util Response to Generic Ltr 83-28 Re post-trip Review - Data & Info Capability ML20062E8331990-10-31031 October 1990 Monthly Operating Rept for Oct 1990 for Yankee Atomic Power Station ML20058G1471990-10-31031 October 1990 Vol 2 to Star Methodology Application for PWRs Control Rod Ejection Main Steam Line Break ML20058C4061990-10-22022 October 1990 Safety Evaluation Supporting Amend 137 to License DPR-3 ML20062B6751990-09-30030 September 1990 Monthly Operating Rept for Yankee Atomic Power Station for Sept 1990 ML20059G2411990-09-0606 September 1990 Safety Evaluation Supporting Amend 135 to License DPR-3 ML20059E3071990-08-31031 August 1990 Safety Assessment of Yaec 1735, Reactor Pressure Vessel Evaluation Rept for Yankee Nuclear Power Station. Detailed Plan of Action W/Listed Elements Requested within 60 Days After Restart to Demonstrate Ability to Operate Longer ML20059E8001990-08-31031 August 1990 Monthly Operating Rept for Aug 1990 for Yankee Atomic Power Station ML20058P7841990-08-14014 August 1990 Part 21 Rept Re Misapplication of Fluorolube FS-5 Oil in Main Steam Line Pressure Gauges.All Four Indicators Replaced W/Spare Gauges Which Utilize High Temp Silicone Oil ML20058N6581990-08-13013 August 1990 Special Rept Re Diesel Fire Pump & Tank Inoperable for Greater than Seven Days for Draining,Cleaning & Insp.During Period Redundant Pumping Capacity Available Via Two Remaining Electric Driven Fire Pumps ML20058L0321990-08-0202 August 1990 Safety Evaluation Supporting Amend 133 to License DPR-3 ML20058L6651990-08-0202 August 1990 Safety Evaluation Supporting Amend 134 to License DPR-3 ML20056A1961990-08-0101 August 1990 Special Rept:Two Fire Pumps Inoperable at Same Time.Caused by Necessity to Accomplish Surveillance to Verify Capability to Start Pump on Emergency Diesel Generator 3 & Planned 18-month Insp of Diesel Per Tech Specs ML20055G6801990-07-31031 July 1990 Yankee Plant Small Break LOCA Analysis ML20055G7011990-07-31031 July 1990 Yankee Nuclear Power Station Core 21 Performance Analysis ML20055E1591990-07-31031 July 1990 Reactor Pressure Vessel Evaluation Rept ML20055J3221990-07-25025 July 1990 Decommissioning Funding Assurance Rept & Certification ML20055G7051990-07-19019 July 1990 Rev 0 to Yankee Cycle 21 Core Operating Limits Rept ML20055F6751990-06-30030 June 1990 Monthly Operating Rept for June 1990 for Yankee Atomic Power Station 1999-08-31
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- i Telephone (617) 872-8100 TWX 710-380 7619 YANKEE ATOMIC ELECTRIC COMPANY e
1671 Worcester Road, Framingham, Massachusetts 01701 April 26, 1988 FYR 88-56 United States Nuclear Regulatory Commission Office of Inspection and Enforcement Region I 475 Allendale Road King of Prussia, PA 19406 Attention: Mr. William T. Russel.1 Regional Administrator
Reference:
(a) License No. DPR-3 (Docket No. 50-29)
Subject:
Notification of Potential Existence of a Design Defect in Accordance with 10CFR21.21
Dear Sir:
In accordance with the provisions of 10CFR21, Section 21, we are hereby notifying you that we have obtained information indicating that a design defect may exist with respect to Automatic Switch Company Tripoint SB12BMR/TL10A22 pressure switches.
Enclosure I to this letter documents the details of this evaluation.
Should you have any questions regarding this matter, please contact me.
Very truly yours, YANKEE ATOMIC ELECTRIC COMPANY lq}
ohn DeVincentis Vice President JDV/25.560 Enclosure
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- ENCLOSURE I Page 1 of 2 Company Informing the Commission: Yankee Atomic Electric Company 1671 Worcester Road Framingham, Massachusetts -07101 Facility: Yankee Nuclear Power Station Star Route Rowe, Massachusetts 01367 Component: ASCO Tripoint SB12BMR/TL10A22 Pressure Switch Firm Supplying Components: Automatic Switch Company (ASCO)
Florham Park, New Jersey Nature of Defect on December 3, 1987, with the plant in Mode 1 at 100% power, five of the twelve main steam line isolation valve pressure switches were found during monthly surveillance to be out of Technical Specification tolerance (Technical Specification Table 3.3-2, Item 3.a). Of five pressure switches that failed the surveillance, three were adjusted back to the required trip setpoint. The remaining two (MS-PS-13 and MS-PS-31) were replaced in kind because of their failure to operate properly.
On April 5, 1988, the two failed switches (MS-PS-13 and MS-PS-31) as well as two other switches (MS-PS-24 and MS-PS-34 which had been replaced for deadband widening and setpoint drift on March 10, 1988 and March 25, 1988 respectively) were disassembled and inspected by ASCO in the presence of Yankee Atomic Electric Company (YAEC) personnel. This inspection revealed the polyurethane disc, which acts as a buffer to protect the process sensing viton diaphragm from adverse action of the piston had, in each of four switches, "extruded" into the area between the piston and the cylinder walls. The degree of extrusion varied from switch to switch witn at least one failed switch showing material over the top of the piston. Although no final report has, to date, been received from ASCO, this extrusion of material is currently considered as the cause of switch failure.
On April 6, 1988 inspection of two additional switches (MS-PS-32 and MS-PS-33 which were removed and replaced for deadband widening on March 26, 1988) noted the same extrusion mechanism as those pressure switches inspected at ASCO on April 5, 1988.
Date of Incident The pressure switch failure of MS-PS-13 and MS-PS-31 occurred on December 3, 1987. Licensee Event Report 50-29/87-15 was submitted on December 31, 1987. The potential Part 21 Report Evaluation was initiated on April 11, 1988.
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ENCLOSURE I Page 2 of 2 (Continued) r Number of Components
'YAEC has twelve safety-related ASCO Tripoint SB12BMR/TL10A22 pressure switches in service in the Main Steam Isolation System.
Corrective Action After the initial discovery of the failed pressure switches the routine surveillance cycle was increased from monthly to semimonthly and the manufacturer (ASCO) was contacted to assist in determining the cause of the pressure switch failures. Testing and inspection of failed pressure switches indicates the pressure switch failures and deadband widening are due to the generic failure / extrusion of the polyurethane disc. This type of occurrence has never been observed by ASCO.
YAEC has taken the following actions to ensure the pressure switch failure mode does not create a substantial safety hazard:
- 1. Replace in kind the remaining six pressure switches (MS-PS-11, 12, 14, 21, 22, and 23) as soon as practicable.
- 2. Perform the survelliance cycle biweekly until further evaluations indicate the switches are experiencing proper actuation.
- 3. Cycle each pressure switch three times during each surveillance.
Related Advice Our evaluation has determined that a significant safety hazard does not exist at Yankee Nuclear Power Station since we have taken appropriate corrective actions on all the ASCO Tripoint SB12BMR/TL10A22 pressure switches. However, ASCO appears not to have given notification to other utilities of the possible pressure switch failure mechanism. Therefore, this Part 21 is being submitted to forewarn other utilities of this potential problem.
It is recommended that utilities review this information for applicability to their locations.
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