Introduction to the Basic Structure and Classification of Box Type Quenching Furnaces

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 a cylindrical deep well for the furnace body, 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. Box-type quenching furnaces are generally installed below the workshop floor level, but they can also be installed 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, and well-type gas carburizing furnace, etc. 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 units installed tangentially along the inner wall of the furnace chamber, arranged uniformly in height in layers or in a spiral pattern to prevent direct flame impingement on the workpiece, ensuring uniform furnace temperature. When used for low-temperature tempering or when oil is used as the cooling medium, 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.