Pull-through Furnaces

Pull-through furnaces are used mainly in the heat treatment of wire and strip in many different forms. The material can be stainless steel, carbon steel and high speed steel.

The processes may be austenitizing and - depending on downstream equipment - patenting, hardening, recrystallization, tempering, etc.

As a rule protective gas in the form of nitrogen, nitrogen/hydrogen in different mixture ratios and pure hydrogen are used. Within the steel industry, in the manufacturing process of strip, the furnaces are usually operated without protective gas.

The furnaces are usually horizontal or vertical, but can also be a combination of those. The furnaces are usually long/high and lengths of between 6 and 100 m occur.

In the heat treatment of wire, profiles and narrow strip many parallel wire/strips are run in the same furnace. They are often led through tubes or muffles of different dimensions.

The benefits of these furnaces is that the furnace itself has no moving parts. In general, the material is uncoiled before entering the furnace and then coiled up again after heat treatment.

Modern furnaces of this type are generally well insulated and  designed so that elements rarely need replacing or can be exchanged during operation.