The roller hearth furnace conveys the work directly on the hearth rollers. Work can also be processed in baskets or on trays which are conveyed on the rollers. Quench systems and cooling systems can also be provided.
Furnaces can be designed for use with or without atmosphere. Heating systems can be direct open fired, indirect fuel fired or electrically heated. Furnaces can be lined with refractory or with ceramic fiber depending on the application. furnaces. The high temperature consistency and low energy consumption of these furnaces, normally gas-fired, ensure reproducible quality and short treatment times.
The processes used for heat treating non-alloyed and alloyed carbon steel pipes at temperatures around 2200° F include carbonitriding, carburizing, stress relieving, hardening, normalizing, recrystallizing, normalizing, sintering, soft annealing and spheroidizing in indirectly fired continuous roller hearth furnaces.