Lindberg/MPH shipped two electrically heated nitrogen pit furnaces to a manufacturing company. The furnaces are configured for process applications requiring a maximum furnace temperature of 1250°F (677°C) in a nitrogen atmosphere. The load space is 39 inches in diameter and 49 inches deep, but the chamber is larger and provides clearance for loading baskets and fixtures. There is a maximum workload of 4,980 pounds. A set of type-K thermocouples are installed to measure the temperature of the atmosphere before entering the workload. One thermocouple is for the process temperature controller, and the other is for the high-temperature controller.
According to Riverside, Mich.-based LindbergMPH, which designed and built the units, the furnaces feature a retort structured as a cylindrical shell with a solid bottom. They also include a sealing trough at the top that is lined with a gasket, which seals with the furnace cover lid. With this specific furnace, a fan circulates heat and atmosphere evenly throughout the work chamber.
The outer shell is constructed of heavy-gauge steel and reinforced with structural steel members. The entire shell is supported by heavy-gauge steel legs and includes refractory lining composed of thermally efficient ceramic-fiber insulating modules.