Steve Benson is not an electrical or mechanical engineer. But he has been working at a steel mill for 24 years and has become an expert in “Making Good Electrical Connections,” the topic he will be presenting at the Finepoint Circuit Breaker Test and Maintenance Training Conference in October. He has been the melt shop electrical supervisor at the Nucor Steel (formerly Auburn Steel Co.) facility since 1998.

Benson will share his experiences with electrical connections of furnace transformer vacuum switch buss connections, which are Joslyn switches.

“We were using aluminum bolts and flat washers with bellvil washers and tightening until they were flat,” Benson said. All of the equipment, he said, is mostly original from 1974.

“Our vacuum bottle failure rate was relatively high, about five or six switch replacements a year. It was recommended by Cecil Wriston of Vacuum Electric Switch Co. to switch to stainless bolts and flat washers with the bellvil washer for tightness,” he said.

The failure rate of the switches then reduced in the first year by 50% or more. These switches on average cost around $5000 to repair, not including the downtime, which is around 30 to 60 minutes to change out a switch.

“Our failure rate has improved to about one or two vacuum bottles a year on average,” Benson said. Benson will be on hand to discuss his experiences at the conference.