The box-type quenching furnace is a periodic operation furnace suitable for heat treatment of rod and long shaft parts. The structure of the box-type quenching furnace is: the furnace body is a deep well in the shape of a cylinder, with workpieces vertically loaded into the furnace by a crane for heating. The fuel typically used is coal gas or oil. When electric power is used as the heat source, it is called a well-type resistance furnace. The box-type quenching furnace is usually installed below the factory floor level, but it can also be placed above the floor level or half above and half below.

The names of box-type quenching furnaces include forced convection box-type quenching furnace, natural convection box-type quenching furnace, well-type gas carburizing furnace, and so on. Box-type quenching furnaces can be powered by gas or liquid fuel, as well as electric heating. When using gas fuel, there are typically multiple small-burner nozzles installed tangentially along the inner wall of the furnace chamber, arranged uniformly in height in layers or in a spiral to avoid direct flame impingement on the workpiece, ensuring uniform furnace temperature. When used for low-temperature tempering or when oil is used as the softening material, a thin muffle wall is built inside the furnace chamber to separate the combustion space from the heating space, but box-type quenching furnaces with muffle walls consume fuel more efficiently.