Part 21 Report - 1997-010

LICENSEE: ITT INDUSTRIES SITE: ITT INDUSTRIES EN NUMBER:31570 DOCKET: EVENT DATE: 01-10-97 RX TYPE: EVENT TIME: 16:07 VENDORS: NOTIFY DATE: 01-10-97 EMERGENCY CLASS: N/A REGION: 4 STATE: CA TIME: 16:07 OPS OFFICER: JOHN MacKINNON 10 CFR SECTION: CDEG 21.21(c)(3)(i) DEFECTS/NONCOMPLIANCE A SITUATION HAS BEEN DISCOVERED (IN THE BARTON MODEL 753 GAGE PRESSURE ELECTRONIC TRANSMITTERS) THAT ITT BARTON BELIEVES MAY REPRESENT A SUBSTANTIAL HAZARD IN SOME OF THESE INSTRUMENTS THAT ITT HAS MANUFACTURED. THIS HAZARD IS SULFUR INDUCED CORROSION OF THE #40 AWG COPPER STRAIN GAGE LEAD WIRES AND THE BERYLLIUM COPPER LINK CLIP. ITT INDUSTRIES (ITT BARTON) LOCATED AT 900 S. TURNBULL CANYON RD., P.O BOX 1882, CITY OF INDUSTRY, CA. NOTIFIED WESTINGHOUSE ENERGY CENTER LOCATED AT 4350 NORTHERN PIKE, MONROVILLE, PA. OF THIS POTENTIAL 10 CFR PART 21 NOTIFICATION ON 01/10/97. ITT BARTON SUPPLIES MODEL 753 GAGE PRESSURE ELECTRONIC TRANSMITTERS TO THE COMMERCIAL NUCLEAR POWER INDUSTRY FOR USE IN SAFETY RELATED APPLICATIONS THROUGH WESTINGHOUSE NUCLEAR ENERGY. A SITUATION HAS BEEN DISCOVERED THAT ITT BARTON BELIEVES MAY REPRESENT A SUBSTANTIAL SAFETY HAZARD IN SOME OF THESE INSTRUMENTS THAT THEY HAVE MANUFACTURED. THIS SITUATION INVOLVES SULFUR INDUCED CORROSION OF THE #40 AWG COPPER STRAIN GAGE LEAD WIRES AND THE BERYLLIUM COPPER LINK CLIP. UNTIL RECENTLY, ITT BARTON WAS NOT ABLE TO ASCERTAIN THE SOURCE OF THE SULFUR CONTAMINATION AND BELIEVED THAT THE LIMITED OCCURRENCES OF THIS PROBLEM ORIGINATED OUTSIDE THE FACTORY. ITT BARTON UNCOVERED THAT THE CORK GASKET USED WITH THE BOURDON TUBE TRANSDUCER HOUSING CAUSED CORROSION OF COPPER AND COPPER ALLOY PARTS. IN ADDITION, INTERVIEWS WITH INSTRUMENT ASSEMBLY PERSONNEL UNCOVERED A SITUATION WHICH INDICATED THAT SOME LINK ADJUST ASSEMBLIES USED IN THE MODEL 753 TRANSMITTER MAY HAVE BEEN CONTAMINATED WITH DOW CORNING MOLYKOTE (MOLYBDENUM DISULFIDE). CORRECTIVE ACTIONS IMPLEMENTED IN THE FACTORY INCLUDED REMOVAL OF ALL GASKETS OF CONCERN, SUBSTITUTION OF A GASKET MADE FROM A MORE STABLE MATERIAL, ASSEMBLY PROCEDURE UPGRADES, OPERATOR TRAINING, AND CLEANING OF ALL EXISTING LINK ADJUST ASSEMBLIES. THE EXISTENCE OF THE SULFUR INDUCED CORROSION CAN BE SEEN IN AN OPERATING INSTRUMENT IN THE FORM OF ABNORMAL DRIFT(i.e., DRIFT IN EXCESS OF NORMALLY EXPERIENCED DRIFT FOR THE PARTICULAR UNIT MONITORED OVER A PERIOD OF DAYS AT STEADY STATE CONDITIONS). THE DIRECTION OF THE STRAIN GAGE LEAD WIRE CORROSION DRIFT CAN BE HIGH OR LOW DEPENDING ON THE CORROSION RATE APPLICABLE TO THE COMPRESSION OR TENSION STRAIN GAGE LEADS. LINK CLIP DRIFT DIRECTION IS ALWAYS NEGATIVE. THE ELECTRICAL LEAD CORROSION DRIFT IS CAUSED BY THE INCREASE IN RESISTANCE OF THE CIRCUIT AS THE CORROSION REDUCES THE DIAMETER OF THE LEAD WIRES WHILE THE LINK CLIP CORROSION DRIFT IS CAUSED BY MATERIAL STRETCHING AS THE LINK CLIP THICKNESS IS REDUCED. THERE IS NO DIFFERENCE BETWEEN A SAFETY RELATED AND A NON SAFETY RELATED MODEL 753 WITH RESPECT TO THIS CORROSION CONCERN. THIS CONCERN IS LIMITED TO THE MODEL 753 TRANSMITTER BECAUSE OF THE USAGE OF THE SULFUR CONTAMINATED COMPONENTS. NUCLEAR POWER PLANTS OF CONCERN ARE: 1) SOUTH CAROLINA ELECTRIC & GAS (V.C. SUMMER ), 2) DUQUESNE LIGHT (BEAVER VALLEY), AND PACIFIC GAS & ELECTRIC (DIABLO CANYON).

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