Shaft furnace is a periodic operation furnace, which is suitable for the heat treatment of rod and long shaft parts. The structure of the pit furnace is: the furnace body is a cylindrical deep well, and the workpiece is vertically loaded into the furnace by a special crane. The fuels used are usually gas and oil. When electricity is used as a heat source, it is called a well-type resistance furnace. Well type furnace is generally placed below the floor plane of the workshop, there are also placed above the ground plane, or half above the ground plane. Well furnace names are: forced convection well furnace, natural convection well furnace, well gas carburizing furnace and so on.