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Category:DEFICIENCY REPORTS (PER 10CFR50.55E & PART 21)
MONTHYEARML20236N6751998-07-0909 July 1998 Part 21 & Deficiency Rept Re Notification of Potential Safety Hazard from Breakage of Cast Iron Suction Heads in Apkd Type Pumps.Caused by Migration of Suction Head Journal Sleeve Along Lower End of Pump Shaft.Will Inspect Pumps ML20140A9661997-05-29029 May 1997 Part 21 Rept Re Ksv Emergency Diesel Generator Power Piston Failure.Caused by Jacket Water in Combustion Chamber. Recommends That Users Verify That Crown Thickness at Valve Cutout Be 100 Minimum ML20137G6261997-03-25025 March 1997 Svcs Part 21 Rept Re Emergency Generators Installed at Zion Station Which Developed Significant Drop in Crankcase Lube Oil Level.Caused by Crack in Liner Wall,Allowing Jacket Water to Enter Chamber ML20117G4641996-05-14014 May 1996 Part 21 Rept Re Cooper Bessemer Reciprocating Products,Div of Cooper Cameron Corp,Issued Ltr to Define Utils/Plants Containing Similar Equipment as Supplied on Cooper Bessemer Ksv & Enterprise Dsr EDGs ML18017A0421992-12-14014 December 1992 Suppl to 921127 Part 21 Rept Re High Air Concentration in Reactor Bldg Making Area Uninhabitable for Retrieving Air Filters,Per NUREG-0737,Item II.F.1.Util Current Position Re Fuel Pool Cooling Issues Contrary to Reg Guide 1.3 ML18026A2481992-11-27027 November 1992 Part 21 Rept Re Substantial Safety Hazard in Design of Facility for Loss of Normal Spent Fuel Pool Cooling ML19325C9521989-09-29029 September 1989 Part 21 Rept Re Potential Common Failure of SMB-000 & SMB-00 Cam Type Torque Switches Supplied Prior to 1981 & 1976. Vendor Recommends That Switch W/Fiber Spacer Be Replaced ML20211P7211987-02-23023 February 1987 Part 21 Rept Re Rockbestos Coaxial Cable Used in Sorrento Electronics Digital & Analog high-range Radiation Monitor. Insulation Resistance at High Temp Not High Enough for Ion Chamber & Associated Electronics to Operate Properly ML20212E5631986-12-19019 December 1986 Part 21 Rept Re Valve Problem.Houghto 620 Lubricant Attacks & Degrades Aluminum in Valves.Valves Have Been or Being Rebuilt ML20215G5351986-10-10010 October 1986 Part 21 Rept Re Vendor Tests of air-operated Diaphragm Valves Revealing Natural Frequencies Less than Required Values of 33 Hz.Initially Reported on 841227.No Adverse Effects Noted During Testing ML20203F6471986-07-23023 July 1986 Part 21 Rept Re Morrison-Knudsen Undersized Welds at Plant. Initially Reported on 860630.Study Concluded That Welds Not Cause for Failure of Plant.Welds Will Be Repaired by Vendor ML20206S0841986-06-30030 June 1986 Part 21 Rept Re Possible Cut Wires in Wire Harness of Bbc Brown Boveri K600/K800 Circuit Breakers.Initially Reported on 860509.Safety Implications Listed.Gear Guard Designed to Prevent Cut Wires ML20197H1991986-05-0909 May 1986 Part 21 Rept Re Hilti Fastening Sys Anchor Bolts Failing to Meet Average Ultimate Tensile Loads.Initially Reported on 860509.Design Review & Resolutions of Installed Items Underway ML20154K3611986-03-0505 March 1986 Part 21 Rept Re Possible Wiring Defect in Fabricated Primer Chamber Assemblies for Standby Liquid Control Valves. Initially Reported on 860214.Listed Corrective Actions Will Be Completed by 860328 ML20140A5281985-12-19019 December 1985 Part 21 Rept Forwarding Ltr Sent to Customers Re Check Valves Missing Lock Welds on Hinge Supports or Hinge Support Capscrews,Per 851121 Request.List of Customers Receiving Ltr Also Encl ML20138F5631985-12-0505 December 1985 Part 21 Rept Re Failure to Perform Calculations for Two 6-inch Insp Nozzles.Purchaser Notified Not to Place Vessels Into Svc.Design Spec & Rept Will Be Revised to Include Insp Openings ML20134A9511985-10-0808 October 1985 Part 21 Rept Re Defect in Valve Stems Bearing Heat Number 3876.Entire Stem/Disc Assembly Will Be Replaced Upon Request.Replacement Stem Assembly Will Be Supplied Under Unique Part Number 106626-10 ML20134B0031985-09-26026 September 1985 Part 21 Rept Re Cracked Stem Assembly Detected in 3/4-inch Yarway Welbond Valve at non-nuclear Facility.Investigation Revealed Leakage Caused by Void in Bar Stock.Valves Sold to Nuclear Facilities Contained Stems.Review Continuing ML20137G1121985-08-22022 August 1985 Part 21 Rept Re Separation of Piston from Connecting Rod on Cooper-Bessemer Reciprocating Div Ksv Engine.Initially Reported on 850304.Engine Returned,Rebuilt & Inspected.No Future Problems Foreseen ML20108B5611985-03-0404 March 1985 Part 21 Rept Re Defective Engine Used for Driving Standby Power Generator at Facility.Caused by Loosened Attachments Separating Piston from Rod.Engine Will Be Repaired Prior to Installation PLA-2355, Revised Final Deficiency Rept Re RHR Throttling Valves. Initially Reported on 820316.Reversal of Valve Disks & Valves No Longer Considered Necessary1984-12-10010 December 1984 Revised Final Deficiency Rept Re RHR Throttling Valves. Initially Reported on 820316.Reversal of Valve Disks & Valves No Longer Considered Necessary PLA-2230, Final Deficiency Rept Re Electrical Separation Inside Multiple Div Junction & Pull Boxes.Initially Reported on 830721.Drawings Revised to Clarify &/Or Define Sparation Requirements for Use W/Junction & Pull Boxes1984-06-28028 June 1984 Final Deficiency Rept Re Electrical Separation Inside Multiple Div Junction & Pull Boxes.Initially Reported on 830721.Drawings Revised to Clarify &/Or Define Sparation Requirements for Use W/Junction & Pull Boxes PLA-2118, Final Part 21/deficiency Rept Re Clamps on CRD Insert/ Withdrawal Lines.Initially Reported on 831209.Outer Pedestal Modified Due to Lack of Sufficient Axial Restraint Capacity of Inner Pedestal Support1984-06-18018 June 1984 Final Part 21/deficiency Rept Re Clamps on CRD Insert/ Withdrawal Lines.Initially Reported on 831209.Outer Pedestal Modified Due to Lack of Sufficient Axial Restraint Capacity of Inner Pedestal Support PLA-2215, Final Deficiency Rept Re Base Metal Cracking & Bending of Angle Fittings Mfg by Unistrut,Powerstrut & B-Line Used on Class IE Electrical Raceways & Category 1 HVAC Supports. Initially Reported on 840206.Spec Revised1984-06-0101 June 1984 Final Deficiency Rept Re Base Metal Cracking & Bending of Angle Fittings Mfg by Unistrut,Powerstrut & B-Line Used on Class IE Electrical Raceways & Category 1 HVAC Supports. Initially Reported on 840206.Spec Revised PLA-2189, Final Part 21 Rept Re GE Reactor Mode Switch.Initially Reported on 830407.Mode Switch Design Modified,Per Franklin Inst Research Lab Recommendations1984-05-21021 May 1984 Final Part 21 Rept Re GE Reactor Mode Switch.Initially Reported on 830407.Mode Switch Design Modified,Per Franklin Inst Research Lab Recommendations ML20084C2851984-04-19019 April 1984 Final Deficiency Rept Re Waterhammer Loading of Scram Discharge Vol (SDV) Vent & Drain Lines After Opening SDV Vent & Drain Valves on Scram Reset.Initially Reported on 830628.Vent Line Supports Will Be Modified Prior to 841231 PLA-2180, Final Part 21/deficiency Rept Re Improper Relief Valve Settings,Design Pressures & Temps.Initially Reported on 831118.Calculations Performed Assure Lines Adequate for Intended Svc1984-04-19019 April 1984 Final Part 21/deficiency Rept Re Improper Relief Valve Settings,Design Pressures & Temps.Initially Reported on 831118.Calculations Performed Assure Lines Adequate for Intended Svc PLA-2166, Part 21 Rept Re Failure of Crosby IMF-2 Solenoids Supplied by Ge.Initially Reported on 840403.Licensee & GE Jointly Developed Test Procedures to Bench Test Spares & Solenoids on Both Units.Testing Complete on Unit 11984-04-0909 April 1984 Part 21 Rept Re Failure of Crosby IMF-2 Solenoids Supplied by Ge.Initially Reported on 840403.Licensee & GE Jointly Developed Test Procedures to Bench Test Spares & Solenoids on Both Units.Testing Complete on Unit 1 PLA-2137, Revised Final Deficiency Rept Re Fraying of Hydrogen Recombiner Cables.Initially Reported on 830728.Fraying Caused by Handling Process for Shipment,Installation & Testing.Cables Repaired1984-03-23023 March 1984 Revised Final Deficiency Rept Re Fraying of Hydrogen Recombiner Cables.Initially Reported on 830728.Fraying Caused by Handling Process for Shipment,Installation & Testing.Cables Repaired PLA-2140, Second Interim Deficiency Rept Re Base Metal Cracking in Angle Fittings.Initially Reported on 840206.Angle Fittings Added to Defective Device List & Conduit Installation Spec Revised.Also Reportable Per 10CFR211984-03-22022 March 1984 Second Interim Deficiency Rept Re Base Metal Cracking in Angle Fittings.Initially Reported on 840206.Angle Fittings Added to Defective Device List & Conduit Installation Spec Revised.Also Reportable Per 10CFR21 PLA-2074, Third Interim Deficiency Rept Re Electrical Separation Inside Multiple Division Junction & Pull Box.Initially Reported on 830721.Design Basis Criteria & Barrier Configuration Established.Also Reported Per Part 211984-03-20020 March 1984 Third Interim Deficiency Rept Re Electrical Separation Inside Multiple Division Junction & Pull Box.Initially Reported on 830721.Design Basis Criteria & Barrier Configuration Established.Also Reported Per Part 21 PLA-2120, Interim Part 21/deficiency Rept Re Base Metal Cracking in Fittings Used on Class IE Electrical Raceways & HVAC Supports.Initially Reported on 840206.Final Rept Expected Prior to Initial Criticality1984-03-0707 March 1984 Interim Part 21/deficiency Rept Re Base Metal Cracking in Fittings Used on Class IE Electrical Raceways & HVAC Supports.Initially Reported on 840206.Final Rept Expected Prior to Initial Criticality PLA-2103, Final Deficiency Rept Re Cavitation of Jet Pumps Due to Induction Heating Stress Improvement Cooling.Initially Reported on 831206.No Erosion Found.Also Reportable Per Part 21.Item Not Reportable Per 10CFR50.55(e)1984-03-0606 March 1984 Final Deficiency Rept Re Cavitation of Jet Pumps Due to Induction Heating Stress Improvement Cooling.Initially Reported on 831206.No Erosion Found.Also Reportable Per Part 21.Item Not Reportable Per 10CFR50.55(e) PLA-2075, Second Interim Deficiency Rept Re Improper Relief Valve Setting,Design Pressures & Design Temp within Several Sys. Initially Reported on 831118.Spec M-199 Revised & Code Data Repts Amended.Also Reported Per Part 211984-03-0202 March 1984 Second Interim Deficiency Rept Re Improper Relief Valve Setting,Design Pressures & Design Temp within Several Sys. Initially Reported on 831118.Spec M-199 Revised & Code Data Repts Amended.Also Reported Per Part 21 PLA-2089, Final Deficiency & Part 21 Repts Re Safety Parameter Display Sys Technology Energy Corp Model 156 Isolators.Initially Reported on 840106.Non-IE Power Supply Will Be Provided for Isolator Prior to End of First Refueling1984-02-27027 February 1984 Final Deficiency & Part 21 Repts Re Safety Parameter Display Sys Technology Energy Corp Model 156 Isolators.Initially Reported on 840106.Non-IE Power Supply Will Be Provided for Isolator Prior to End of First Refueling PLA-2062, Final Deficiency Rept Re Bechtel Failure to Accomplish Design Verification of safety-related Power & Control Cables.Caused by Failure to Complete Required Cable Length Verification.Deficiency Not Reportable Per 10CFR50.55(e)1984-02-13013 February 1984 Final Deficiency Rept Re Bechtel Failure to Accomplish Design Verification of safety-related Power & Control Cables.Caused by Failure to Complete Required Cable Length Verification.Deficiency Not Reportable Per 10CFR50.55(e) PLA-2073, Final Part 21 Rept Re Hydrogen Catalyst Used in Comsip Custom Line Model K-IV Containment Gas Monitoring Panels. Initially Reported on 840113.Comsip Redesigned Catalyst Will Be Installed1984-02-13013 February 1984 Final Part 21 Rept Re Hydrogen Catalyst Used in Comsip Custom Line Model K-IV Containment Gas Monitoring Panels. Initially Reported on 840113.Comsip Redesigned Catalyst Will Be Installed PLA-2063, Interim Part 21 Rept Re Safety Parameter Display Sys Model 156 Isolators Mfg by Technology for Energy Corp (Tec). Initially Reported on 840106.All Tec Isolators Reviewed for Corrective Actions1984-02-0606 February 1984 Interim Part 21 Rept Re Safety Parameter Display Sys Model 156 Isolators Mfg by Technology for Energy Corp (Tec). Initially Reported on 840106.All Tec Isolators Reviewed for Corrective Actions PLA-2045, Followup Deficiency Rept Re Mod of RHR Globe Valves F017A & FO17B to Enable Valves in Shutdown Cooling Mode to Perform W/O Adverse Cavitation & Vibration at Low Flow Rates.Initially Reported on 811112.Valves Replaced1984-01-25025 January 1984 Followup Deficiency Rept Re Mod of RHR Globe Valves F017A & FO17B to Enable Valves in Shutdown Cooling Mode to Perform W/O Adverse Cavitation & Vibration at Low Flow Rates.Initially Reported on 811112.Valves Replaced PLA-2033, Interim Deficiency Rept Re Clamps on Control Rod Drive Insert/Withdraw Lines Not Providing Axial Restraint. Initially Reported on 831209.Design Mod to Pedestal Support Initiated.Also Reportable Per Part 211984-01-12012 January 1984 Interim Deficiency Rept Re Clamps on Control Rod Drive Insert/Withdraw Lines Not Providing Axial Restraint. Initially Reported on 831209.Design Mod to Pedestal Support Initiated.Also Reportable Per Part 21 PLA-2026, Interim Deficiency Rept Re GE Reactor Mode Switch.Proposed Redesign of Mode Switch by GE Rejected,Based on Results of Testing Conducted at Franklin Inst Research Lab.Alternate Switch Ordered Through Electroswitch.Final Rept by Apr 19841984-01-12012 January 1984 Interim Deficiency Rept Re GE Reactor Mode Switch.Proposed Redesign of Mode Switch by GE Rejected,Based on Results of Testing Conducted at Franklin Inst Research Lab.Alternate Switch Ordered Through Electroswitch.Final Rept by Apr 1984 PLA-2009, Final Deficiency Rept Re Standby Gas Treatment Sys (SGTS) Performance Not as Described in Fsar.Fsar Change Prepared to Indicate SGTS May Be Required to Maintain Secondary Containment Integrity1984-01-0909 January 1984 Final Deficiency Rept Re Standby Gas Treatment Sys (SGTS) Performance Not as Described in Fsar.Fsar Change Prepared to Indicate SGTS May Be Required to Maintain Secondary Containment Integrity PLA-1990, Final Deficiency Rept Re Isolation of Nitrogen Makeup Sys. Permanent Mod Consists of Rerouting Drywell & Wetwell Nitrogen Makeup Lines to Spare Penetrations.Divisionalized Isolation Valves Will Be Installed1983-12-30030 December 1983 Final Deficiency Rept Re Isolation of Nitrogen Makeup Sys. Permanent Mod Consists of Rerouting Drywell & Wetwell Nitrogen Makeup Lines to Spare Penetrations.Divisionalized Isolation Valves Will Be Installed PLA-1946, Interim Deficiency Rept Re Bechtel Failure to Accomplish Design Verification of safety-related Power & Control Cables.Bechtel Completed & Documented Required Cable Length Verification & Calculations1983-12-30030 December 1983 Interim Deficiency Rept Re Bechtel Failure to Accomplish Design Verification of safety-related Power & Control Cables.Bechtel Completed & Documented Required Cable Length Verification & Calculations PLA-1991, Final Deficiency Rept Re Cracks in Pacific Scientific PSA-1 & PSA-3 Snubber Capstan Springs.Caused by Improper Spring Forming.Snubbers Will Be Corrected Prior to Completion of First Refueling Outage.Also Reported Per Part 211983-12-27027 December 1983 Final Deficiency Rept Re Cracks in Pacific Scientific PSA-1 & PSA-3 Snubber Capstan Springs.Caused by Improper Spring Forming.Snubbers Will Be Corrected Prior to Completion of First Refueling Outage.Also Reported Per Part 21 PLA-2000, Interim Deficiency Rept Re Electrical Sys Separation in Multiple Div Pull & Junction Boxes.One Box Identified Containing Redundant Channel C & D Circuits Insufficiently Separated by Approved Barrier1983-12-27027 December 1983 Interim Deficiency Rept Re Electrical Sys Separation in Multiple Div Pull & Junction Boxes.One Box Identified Containing Redundant Channel C & D Circuits Insufficiently Separated by Approved Barrier PLA-2006, Interim Part 21 Rept Re Improper Relief Valve Settings & Design Pressures & Temps Found in Hpci,Rcic,Rhr,Core Spray & Essential Svc Water Sys.Initially Reported on 831118. Hydrotests Performed1983-12-20020 December 1983 Interim Part 21 Rept Re Improper Relief Valve Settings & Design Pressures & Temps Found in Hpci,Rcic,Rhr,Core Spray & Essential Svc Water Sys.Initially Reported on 831118. Hydrotests Performed PLA-1987, Updated Interim Deficiency Rept Re Scram Discharge Vol Vent & Drain Valve Waterhammer.Testing & Subsequent Analysis Will Be Completed in Mar 1984.Util Will Submit Final Rept by Apr 19841983-12-14014 December 1983 Updated Interim Deficiency Rept Re Scram Discharge Vol Vent & Drain Valve Waterhammer.Testing & Subsequent Analysis Will Be Completed in Mar 1984.Util Will Submit Final Rept by Apr 1984 PLA-1967, Final Deficiency Rept Re Suppression Pool Temp Monitoring Sys (Spotmos).Initially Reported on 821015.Modified Installation Configuration Tested.Review of Test Results Will Be Completed by End of Mar 19841983-12-13013 December 1983 Final Deficiency Rept Re Suppression Pool Temp Monitoring Sys (Spotmos).Initially Reported on 821015.Modified Installation Configuration Tested.Review of Test Results Will Be Completed by End of Mar 1984 PLA-1968, Final Deficiency & Part 21 Repts Re Final Design of GE 7700 Series 250-volt Dc Control Ctrs.Plant Operating Procedures Revised to Include Methods of Clearing Obstructions as Provided by GE & Exam & Reforming of Draw Out Contacts1983-12-0505 December 1983 Final Deficiency & Part 21 Repts Re Final Design of GE 7700 Series 250-volt Dc Control Ctrs.Plant Operating Procedures Revised to Include Methods of Clearing Obstructions as Provided by GE & Exam & Reforming of Draw Out Contacts 1998-07-09
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217A9931999-09-30030 September 1999 NRC Regulatory Assessment & Oversight Pilot Program, Performance Indicator Data ML17146B1741999-08-0303 August 1999 GL 96-06 Risk Assessment for Sses. ML20206D3331999-04-27027 April 1999 SER of Individual Plant Examination of External Events Submittal on Susquehanna Steam Electric Station,Units 1 & 2. Staff Notes That Licensee IPEEE Complete with Regard to Info Requested by Suppl 4 to GL 88-20 ML20195B2381999-03-31031 March 1999 Redacted Version for 10CFR2.790 Request for Decommissioning Status Rept for Sses,Units 1 & 2 ML17164A8451998-10-31031 October 1998 SSES Unit 1 Tenth Refueling & Insp Outage ISI Outage Summary Rept. ML20236N6751998-07-0909 July 1998 Part 21 & Deficiency Rept Re Notification of Potential Safety Hazard from Breakage of Cast Iron Suction Heads in Apkd Type Pumps.Caused by Migration of Suction Head Journal Sleeve Along Lower End of Pump Shaft.Will Inspect Pumps ML20217Q4891998-04-21021 April 1998 Rev 1 to Draft LDCN 2482, FSAR Chapter 13.4 & FSAR Chapter 17.2 Changes to Support ITS Implementation ML18026A4931998-03-30030 March 1998 LER 97-007-01:on 971017,entry Into TS 3.0.3 Occurred to Allow Completion of Surveillance Testing of One Channel of Rbm.Caused by Failure of Components in LPRM Output to Rbm. Submitted TS Change Request to Extend LCO Action Statement ML18026A5401998-02-28028 February 1998 Monthly Operating Repts for Feb 1998 for Susquehanna Steam Electric Station.W/980313 Ltr ML18026A4891997-11-17017 November 1997 LER 97-007-00:on 971017,TS 3.0.3 Entry Voluntarily Made. Caused by Inadequate Post Maint Testing Following Earlier Work Associated W/Components.Failed Components Repaired, Replaced & Testing Completed ML18017A2921997-10-28028 October 1997 1997 Nrc/Fema Observed Exercise. ML17158C1861997-06-0505 June 1997 Proceedings of Intl Topical Meeting on Advanced Reactors Safety Vol II, on 970601-05 ML20140A9661997-05-29029 May 1997 Part 21 Rept Re Ksv Emergency Diesel Generator Power Piston Failure.Caused by Jacket Water in Combustion Chamber. Recommends That Users Verify That Crown Thickness at Valve Cutout Be 100 Minimum ML18026A4781997-03-28028 March 1997 Rev 1 to Application of Anfb to ATRIUM-10 for Susquehanna Reloads. ML20137G6261997-03-25025 March 1997 Svcs Part 21 Rept Re Emergency Generators Installed at Zion Station Which Developed Significant Drop in Crankcase Lube Oil Level.Caused by Crack in Liner Wall,Allowing Jacket Water to Enter Chamber ML20155F7661996-07-25025 July 1996 Partially Deleted Job Number 739619-96, Investigation of E Diesel Breaker Misalignment ML20155F7491996-07-24024 July 1996 Independent Safety Evaluation Svcs Project Rept 3-96, Investigation of E Diesel Generator In-Operability Event ML20117G4641996-05-14014 May 1996 Part 21 Rept Re Cooper Bessemer Reciprocating Products,Div of Cooper Cameron Corp,Issued Ltr to Define Utils/Plants Containing Similar Equipment as Supplied on Cooper Bessemer Ksv & Enterprise Dsr EDGs ML18026A5961996-01-0202 January 1996 LER 95-013-00:on 951119,thermally Induced Pressure Locking of HPCI Valve Occurred Under Bonnet Pressure of 3,000-7,000 Psig.Damaged HPCI Injection Valve repaired.W/960102 Ltr ML18017A0511995-11-30030 November 1995 Monthly Operating Repts for Nov 1995 for SSES Units 1 & 2. W/951215 Ltr ML20092H7641995-08-31031 August 1995 Monthly Operating Repts for Aug 1995 for Susquehanna Ses ML17158A8771995-08-15015 August 1995 Exercise Manual. ML17158A8061995-07-14014 July 1995 Books 1 & 2 of ISI Outage Summary Rept SSES Unit 1 8th Refuel Outage. ML18017A0461995-07-0707 July 1995 LER 95-008-00:on 950609,shift Average Licensed Core Thermal Power Was Exceeded.Caused by Failed Instrumentation Drift. Repaired & Recalibrated Subject Instrumentation ML17164A6631995-04-11011 April 1995 Impact of Extending T-10 AOT from 3 to 7 Days. ML17164A5871995-01-31031 January 1995 Monthly Operating Repts for Jan 1995 for Susquehanna Ses ML18026A5351994-10-31031 October 1994 SSES Unit 1 & 2 MSIV Leakage Alternate Treatment Method Seismic Evaluation. W/One Oversize Drawing ML17158A4821994-08-23023 August 1994 ISI Outage Summary Rept Unit 2 6th Refueling Outage, Books 1 & 2 of 2 ML17158A2391994-04-0505 April 1994 Books 1 & 2 of SSES Unit 1 Seventh Refueling & Insp Outage ISI Outage Summary Rept. ML18017A2701993-12-31031 December 1993 PP&L Annual Rept 1993. ML17158A2651993-12-31031 December 1993 Allegheny Electric Cooperative,Inc Annual Rept 1993. ML17158A1631993-12-0909 December 1993 Remote Indication of Spent Fuel Pool Level & Temperature. ML18026A4281993-08-16016 August 1993 PP&L Response to NRC Concerns Re Loss of Spent Fuel Pool Cooling Following Loca,Sses,Units 1 & 2. ML18026A4261993-06-0909 June 1993 LER 90-007-01:on 900705,primary Power Supply to RPS a Power Distribution Panel Lost When One Electrical Protection Assembly (EPA) Breaker Tripped.Epa Logic Cards Reviewed & RPS Power Supply Will Be redesigned.W/930609 Ltr ML17157C2441993-02-28028 February 1993 Monthly Operating Rept for Feb 1993 for Susquehanna Steam Electric Station,Units 1 & 2 ML18017A2031993-02-0101 February 1993 Books 1 & 2 of Unit 2 Fifth Refueling & Insp Outage,Isi Outage Summary Rept. ML20044C2741993-01-31031 January 1993 Corrected Monthly Operating Rept for Jan 1993 for Susquehanna Steam Electric Station,Unit 2,consisting of Info on Unit Shutdowns & Power Reductions ML17157C3691992-12-31031 December 1992 PP&L Annual Rept 1992. ML20056C3941992-12-31031 December 1992 Allegheny Electric Cooperative,Inc Annual Rept 1992 ML18017A0421992-12-14014 December 1992 Suppl to 921127 Part 21 Rept Re High Air Concentration in Reactor Bldg Making Area Uninhabitable for Retrieving Air Filters,Per NUREG-0737,Item II.F.1.Util Current Position Re Fuel Pool Cooling Issues Contrary to Reg Guide 1.3 ML18026A2481992-11-27027 November 1992 Part 21 Rept Re Substantial Safety Hazard in Design of Facility for Loss of Normal Spent Fuel Pool Cooling ML18026A4231992-11-17017 November 1992 LER 92-016-00:on 920416,discovered That Existing Analysis for Two Spent Fuel Storage Pools Did Not Reflect Current Fuel Design & Plant Operation.Caused by Failure to Modify FSAR Analysis.Fsar Will Be revised.W/921117 Ltr ML17157C1421992-10-21021 October 1992 Engineering Assessment of Fuel Pool Cooling Piping EDR-G20020. ML17157C1411992-08-31031 August 1992 Loss of Fuel Pool Cooling Event Evaluation. ML17157C1401992-08-31031 August 1992 Review of Fuel Pool Cooling During Postulated Off-Normal & Accident Events SSES Units 1 & 2. ML20082C4941992-08-14014 August 1992 Evaluation of Unit 1 & Unit 2 Derating of Power Cables in Raceways Wrapped W/Thermo-Lag Matl ML17157C1381992-07-27027 July 1992 Safety Consequences of Boiling Spent Fuel Pool at Susquehanna Steam Electric Station. ML17157B9331992-07-24024 July 1992 Sixth Refueling & Insp Outage Inservice Insp Outage Summary Rept, Books 1 & 2 ML20097D4681991-12-31031 December 1991 Pennsylvania Power & Light Company,1991 Annual Rept ML18017A0391991-07-26026 July 1991 LER 91-010-00:on 910628,RWCU Isolated on Two Occassions Due to Actuations of Steam Leak Detection Instrumentation. Caused by Design Deficiency & Elevated Ambient Penetration Room Temps.Temp Modules replaced.W/910726 Ltr 1999-09-30
[Table view] |
Text
Revision 1 JN 4'~'- '0'8012 FINAL REPORT ON SPOT-WELDED STRUTS FOR SUSQUEHANNA STEAM ELECTRIC STATION UNITS 1 AND 2 Prepared by:
Checked by:
Approved by:
BECHTEL POWER CORPORATION San Francisco, California September 29, 1978 December 29, 197U (Revision 1)
(P23-9) o80102$
0 l
e
Revision 1 ~
JN 4 >"-" >O JSG'3 2 TABLE OF CONTENTS Section Title ~Pa e 1.0 Purpose 2.0 Spot-welded Struts 3 ~0 Background 4 ' Deficiency and its Safety Implications 5 ' Immediate Action 6.0 Test Program 7 ' Technical Evaluation of Deficiency 8.0 Corrective Action 10 9.0 Repair Methods 10 ' Conclusion 14 ATTACHMENTS Test Report by 'Pittsburgh Testing Laboratory'est Results Specifications
- The Attachments were previously transmitted via PLA-295 dated October 9, 1978 and are not forwarded with this report.
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Revision 1 1 ' PURPOSE The purpose of this report is to provide final data and information as required by 10CFR50.55(e)(3) subsequent to the notification of a reportable deficiency. The subject deficiency is associated with spot/resistance welding in strut material.
2.0 SPOT-WELDED STRUTS 2.1 Struts Basic strut sections are light gage (thickness varying from 0.105 to 0.109 inch) channels manufactured by cold forming mild steel strip. These channel sec- V tions are connected to each other in various configura-tions such as back-to-back, back-to-side, or side-to-side by using a welding process commercially known as spot-welding or resistance welding. The channel sections and built-up sections used on Susquehanna project are either mill-galvanized or hot-dip galvanized after spot-welding and are supplied by Unistrut Corporation, Wayne, Michigan; Power Strut, Division of Van Huffel Tube Corporation, Warren, Ohio; and B-Line Systems Incorporated, Highland, Illinois. These were procured as standard off-the-shelf, items with no formal Quality Assurance. Various configurations used on Susquehanna are given in Figure I.
Strut members are used in field fabricated supports for electrical raceways, HVAC ducts and instrumentation
>e lines. The governing documents are drawing 4 r-'69BQj2..
8856-E-53 for electrical raceways, Specification 8856-M-323-C for HVAC ducts and Drawing 8856-JG-16 for instrumenta-tion.
The supports are designed in accordance with 'Specifi-cation for the Design of Cold-formed Steel Structural Members'1968 Edition), published by American Iron and Steel Institute.
The spot/resistance welding process consists of passing high current through the thicknesses of adjoining plates resulting in metal-to-metal fusion. The quality of a spot weld is dependent on many variables such as pres-sure on the electrode tips, finish of the material, presence of impurities on the material, build-up of zinc and other contaminents on the welding electrodes, contact between joining surfaces, voltage and amperage.
Therefore, unless these parameters are closely moni-tored and controlled, the result may be inadequate fusion.
3.0 BACKGROUND
Since the use of strut material began on the Susquehanna Pro-ject, there were three F
isolated instances when the adjoining channels separated during handling or assembling. These member lengths were rejected.
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evision 1
.)( z-r=. E 8612 However, in recent months there have been significant in-stances on other nuclear projects where inadequate fusion was observed at the weld. spots. As a result of th's', on March 25 and 26, 1978, Bechtel field engineering personnel performed an inspection on Unistrut member P-1004A, Power-strut member PS-3022 and B-Line member B22-X. The tested members were part of installed electrical raceway and HVAC duct supports. .The method of inspection consisted of
'sounding'he members with a ball peen hammer to detect separated spot welds and verification of the separation by insertion of a card between the members at the spot welds.
The inspection indicated a high incidence of spot-welds with inadequate or no fusion. Therefore, Project Quality Assurance (QA) issued Management Corrective Action Report (MCAR) 1-23 on March 28, 1978.
4.0 DEFICIENCY AND ITS SAFETY IMPLICATIONS Based upon the resul'ts of the inspection as described in Section 3.0, it was determined that:
- a. The deficiency is related to spot-welding technique and/or procedure.
- b. The quality of the spot-welding is indeterminate, without further investigation.
Various combinations and configurations of channel struts have been used in the support systems. Individual members
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vision 1 0.8012 have been designed as composite sections for which the con-nection (spot-welding used in this instance) between adjoin-ing channels is relied upon to carry the postulated loads within established design margins. Thus, inadequate fusion at the spot-welding may result in inadequate strength, and may adversely affect the safe operation of the plant under design loading conditions.
5.0 IMMEDIATE ACTION A 'Hold'as imposed on further installation of member P-1004A or its equivalent unless the member was stitch-welded to develop equivalent design strength of the spot-welding.
- 6. 0 TEST PROGRAM 6.1 General.
Although it was determined that a deficiency existed in some spot-welded members, the extent of the de-ficiency was unknown. So the first step was to es-tablish the scope of the problem. Since there is no practical nondestructive I method for examining the sound-ness of spot welds in the erected material, it was de-cided to initiate a destructive test program.
6.2 Basis of Test Pro ram The underlying approach is described below.
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Re sion 1 Jw 4'r-I,:-"Q.Q'lR
- a. Obtain representative samples, selected at random, from the'nstalled and stock material for all shapes and manufacturers.
- b. Perform destructive shear test on the samples to obtain failure loads.
- c. Analyze the test results statistically for each shape and manufacturer to compute corresponding expected strength per spot-weld at a certain confidence level.
- 6. 3 ~sam les Samples were obtained by Bechtel field engineering personnel and sent to a recognized testing laboratory.
Samples were typically 6" long containing two spot-welds.
For the stock material, two samples were obtained from each 20'-0" length and only one sample from any given installed member selected at random. For thc installed material, generally one sample was obtained for every 100 feet of the installed quantity.
- 6. 4 ~Testis Testing was done by Pittsburgh Testing Laboratory (PTL) in Pittsburgh, Pennsylvania. Test method and procedures are fully described in PTL's report. (See Attachment A).
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Revision 1
>e 4-is gasp:g.p 6.5 Statistical Anal sis Based upon the test results, histograms were plotted for each shape and manufacturer. Mean and standard deviation were computed for each case. The test results generally follow the normal distribution.
The expected failure load per spot weld was determined by using the mean of the failure load based upon the test results and subtracting one and a half times the standard deviation. This approach provides more than 90% confidence level for the expected failure load.
Based upon above criteria, the expected failure loads were computed and are given in Table I.
7.0 TECHNICAL EVALUATION
OF DEFICIENCY 7.1 General The technical evaluation in this section is limited to all strut members installed and/or at the jobsite which are not fabricated.
7.2 Desi n Criteria and Theoretical Considerations AISI specification specifies allowable shear strength per spot-weld to be equal to 1.65 kips with a factor of safety of 2.5 for 0.109 inch thickness. This al-lowable shear is based upon "Recommended Practices (9 23-9)
Revision 1 Jg g-(c g,gg.Q'j'f for Resistance Welding," AWS C1.1, by American Welding Society. Based on this criteria, the failure load for a spot should be over 4,000 pounds. However, in light of the problem associated with spot-welding, it is necessary to assess bases of code requirements and evaluate structur al adequacy of the installed material without compromising the basic design philosophy.
The connection pr ovided by spot welds between adjoin-ing channel sections is relied upon to maintain the integrity of the built-up sections. The calculated shear in a spot weld in a member depends upon many variables such as loading, sectional properties, end conditions and if the member is used as a beam, brace, column or tie.
The allowable shear of 1.65 kips/spot specified by the code is the upper limit for designing purpose.
However, from the evaluation point of view, it is more realistic to consider actual maximum design shear cal-culated individually as required for each shape. Sec-ondly, for the strut material (Fy = 33 k.s.i.) the allowable bending stress (Fg ) per code is 20 k.s.i. for 0.105 inch thickness. Therefore, the factor of safety for the bending stress is considered to be 1.65 while for the spot-welds, it is 2.5, which is rather high.
Reason for this could be attributed to many variable, w7 (P23-9)
Revision 1 Ju 4 ra 098012 affecting the weld strength. For the material in ques-tion on Susquehanna, an extensive test program has been carried out and expected failure loads for each shape are well defined. Therefore, it is reasonable to as-sume that a factor of safety of 2.0 for spot-welds, which is still higher than the factory of safety for bending of the strut material would still be adequate and consistent with the basic design philosophy.
7 3 The design of framing members in the suppor t system is based upon allowable shear of 1650 lbs. per spot weld.
Therefore, to maintain a minimum safety factor equal to 2.0, the expected failure load must be 3300 lbs. or greater.
7.3.1 The strut sections with the expected failure load equal to or greater than 3300 lbs/spot weld, are considered to be structurally adequate.
7.3.2 However, for the other sections, further evaluation is necessary.
Design loads on the support systems are governed by many considerations such as type of support, structure, elevation, etc. For individual mem-bers in a support, design shear forces addition-ally depend upon if the members are loaded flex-urally or axially. Et is noted that for flexural members, shear forces are generally high.
Revision 1 JhN g <c g>GOj p For the earlier investigation, a 5'-0" long member 'sup-porting uniformly distributed load was considered to be a representative case for various loading conditions, and member shapes, and comparison was made between com-puted design shears and expected failure loads.
However, in the final analysis, actual design shears were computed in individual members for all support
~ types in various buildings and at different eleva-tions.
These shear values vary considerably; therefore, the existing members, which may be adequate at a certain location, may need strengthening elsewhere depending on the aforementioned variables.'n any case, a fac-tor of safety of 2.0 has been maintained.
- 7. 4 ~Summa r Based upon a factor of safety, of 2.0, all shapes are grouped in three categories.
Cate or I Unistrut: P-5501, P-1001C, P-3301, P-1001A P-1001C3 Powerstrut: PS-151, PS-202 These shapes are structurally adequate and need no repair.
Cate or II Unistrut : P-1001, P-5001 Powerstrut: PS-201, PS-101, PS-204 PS-3080 B-Line : . B-12A These sections are considered deficient at certain locations and need to be repaired as required.
Cate or III Unistrut : P-1004A Powerstrut: PS-3022 B-Line B-22X, B-11A All members of above shapes are to be repaired/
strengthened to provide shear connection capacity equal to twice the design strength required.
8.0 CORRECTIVE ACTION 8.1 General Corrective actions are grouped in several categories. Each category and corresponding action is described below.
8.2 Installed and Stock Material 8.2.1 Powerstrut PS-3022, I
Unistrut P-1004A B-Line B-22X.
Based upon the inspection by Bechtel field engineering personnel, all material of this (P 23-9)
evision l configuration was deemed to be deficient, and will be completely repaired without taking any credit for the existing spot welds.
8.2.2 B-Line B-11A.
Installed and stock quantity for this shape was small; therefore,. no samples were obtained.
In the absence of any test data on the existing spot welds, this section will be repaired to develop required design capacity to meet the design criteria.
8.2.3 Powerstrut
PS-151, PS-202 Unistrut: P-5501, P1001G, P-3301, P-1001A, I
P-1001C3 Based upon the technical evaluation in Section 7.0, existing spot-welding is adequate and will perform satisfactorily under design loads.
Ther efore, no further action is deemed neces-sary.
8.2.4 Powerstrut; PS-201, PS- 101, PS-204, PS-3080 Unistrut: I P-1001, P-5001 B-Line: B12A (P23-1/1)
R evision 1 ig u7 .09 12 These members do not meet the design criteria, therefor e, a detailed re-analysis and redesign has been performed to compute required additional strength and design drawings have been prepared to show the necessary repair details. The re-quired repair will be performed on the installed and stock material. On completion of the repair, the strut material will satisfy the design cri-teria.
8.3 Strut Material to be Received in the Future Until now, the strut material was procured as a stan-dard 'off the shelf'tem. However, in light of the problem experienced with the spot-welding, a new speci-.
fication 8856-C-92 (see Attachment C) was developed for procurement of,all spot-welded struts in the future.
The results of the testing by PTL positively indicate that the spot-welds on a plain material have much higher strength than spot-welds on mill-galvanized material.
Therefore, the specification stipulates that strut material to be coated after spotwelding. In addition to this, to pr ovide a reasonable assur ance of attaining the design strength, the supplier is re-quired to introduce a destructive testing program on the pr oduction samples and no material will be shipped to Susquehanna jobsite unless it meets the acceptance
.criteria. This action should prevent the recur rence of this problem in the future.
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Revision 1 9.0 REPAIR METHODS N 4' Kid+Q3,+r,'.
1 General Construction has been provided the option to select any one of the following methods on a case-by-case basis.
9.
This method is to replace the deficient material with new material to be procured per Specification 8856-C-92 (see Attachment C).
9.3 Mechanical Fasteners Second method is to provide 1/4" dia. self-drilling and self-tapping metal screws to obtain r equired shear strength. These, screws will be procured per Specification 8856-C-91 (see Attachment C). In order to assure strength requirements for the screws, it is required to perform a destructive shear test on samples and each lot must meet the acceptance cr iteria.
In addition to self-drilling and self-tapping screws, other mechanical fasteners are being considered such as pop-rivets or clamps. If these are determined to be technically acceptable, they will be used as alternate to the screws.
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ision 1
- 9. II ~Veldkn Third approach is to provide intermittent .stitch welding at the joint between channels and/or chan-nel and side plate.
10.0 CONCLUSION
On completion of the required repair/replacement of the existing spot-welded struts determined to be deficient, the existing support systems will be structurally ade-quate to satisfy the design requirements. Secondly, pro-curement of new spot-welded strut material per new spec-ification (see Attachment C), will provide adequate as-surance of preventing the recurrence of this problem in the future..
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Hevislon 1
~
FE8 2'80 C 99480 TABLE 1 EXPECTED FAILURE LOADS Standard Expected Failure Load Mean Deviation =A-1.5B Meuufactur er Member (1bs) (1bs) (lbs) Remarks (A) (B)
Unistrut P-1001 4140- 1213 2321 Cat. II P-5501 5499 1229 3656 Cat. I P-5001 4357 -, 1072 Cat. II P-1 001 C 5386 1033 3837 Cat. I P-3301 '465 1025 3928 Cat. I P-1001A 4192 554 3361 Cat. I P-1001C3,5186 629 4243 Cat. I (Back to back)
P-1001C3 5126 458 4439 Cat. I (Back to side)
Powerstrut PS-201 4418, 1194 2627 Cat. II PS-151 5533 892 4195 Cat. I PS-1 01 3855 782 2682 Cat. II PS-204 4150 2233 801 Cat. II I PS-3080 4126 1252 Cat. II (Back to back).
PS-3080 4666 1511 2400 Cat. II (Back to side)
PS-202 5783 3950 Cat, I B12A 3565 1317 1590 Cate II Note'. 1. Above numbers in the table ar e based upon one spot veld.
- 2. For explanation of Remarks" column, refer to section 7.4.
- 3. For shapes in Figure 1 and not in table above (i.e. those in Category III), r efer to section 7.4.
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Revision 1 FIGURE 1 STRUT SHAPES AND IDENTIFICATION
~Sha e K Unistrut P-1001
~Sha e R Powerstrut PS-201 Unistrut P-5501
~Sha e 0 Powerstrut PS-151 Unistrut P-5001 B-Line B-12A Powerstrut PS-101 B-Line B-11A 3~ha e N ~Sha e L Unistrut P-1001C3 Unistrut P-1001C Powerstrut PS-3080 Powerstrut PG-204
.~Sha e N Unistrut P-1004A Powerstrut PS-3022 B-Line , B-22X
~Sha e 0 Unistrut P-1001A Shaue P Powerstrut PS-202 Uuiattut P-3301