Lindberg/MPH shipped three electrically heated, rod-overbend pit furnaces with air-cooled fans. The furnaces will be used to heat treat steel components in a nitrogen atmosphere. Designed to handle a wide range of part sizes, they have a maximum temperature rating of 2000°F (1093°C). Two of the units have work-chamber dimensions of 28 inches in diameter x 36 inches deep with a maximum gross workload of 2,000 pounds. The third furnace has work-chamber dimensions of 60 inches in diameter x 109 inches deep with a maximum gross workload of 20,000 pounds.
All of the pit furnaces have pneumatically operated lids with three-way hand control valves and limit switches that disconnect power to the heating elements when the covers are open. The control systems include Allen Bradley PLCs with a touchscreen operator interface. Eurotherm high-limit controllers, which are installed on each unit, trigger visual and audible alerts in the event the furnace temperature exceeds the setpoint and disconnect the power to the rod-overbend heating elements.
According to Lindberg/MPH, the furnaces have been designed to utilize three independent heating zones for optimal temperature uniformity and meet AMS 2750G, Class 3.