An insulated, the heating system, chamber for placing the job, and a door or various doors for placing the job in place are the necessity of these furnaces. The parts to be heat treated are unloaded and loaded in single batches. A furnace that is easy to utilized, easy to construct in various sizes and having versatility to accommodate various size is a box furnace that could be horizontal rectangular. Many times a flat platform on wheels is utilized to carry the parts in the furnace.
A pit furnace is made in form of a vertical pit underneath the ground level. The parts to be treated are lowered in the pit. Long parts as: shafts, rods, tuning, bars can be suspended in the pit furnace space. These parts are susceptible to distortion whether placed in horizontal position in the box furnace.
A bell furnace does not have lowered and is bottom on the stack of parts to be treated. The furnace chamber could be round or rectangular.
In elevator furnace the parts to be treated are situated on the rolling platform that is rolled in the exact position and lifted to the heating chamber of the furnace. Via placing a quenching tank directly underneath the surface the savings on space and quenching time are made.