· Open Fired Furnaces
· Fluid bed Furnaces
· Oil Tempering furnaces
· Muffle Tube furnaces
· Lead Furnaces
· Pit Type Furnaces
· Bell Type Furnaces
· Dryer Ovens
· Different kinds of heat treatment furnaces are used in the wire lines for the purpose. Open fired furnaces are the most commonly used furnaces for heat treatment of both low and high carbon steel wires. Open flame standing annealing furnaces are the most preferred furnaces by wire manufacturers for their low operating and maintenance costs and ease of use.
· Fluidized beds and lead furnaces are used in the production of low carbon wires. These types of furnaces are also preferred in order to save the building lengths for the galvanizing lines and low acid consumption. Another area where lead furnaces are commonly used is degreasing operations and stress relieving heat treatment applications.
· Muffle ovens are commonly used for heat treatment of stainless steel wires in continuous operation. In this type of furnace, the wires are passed through the pipes placed in the furnace and an inert gas is fed into the pipes to form a protective atmosphere.
· Pit and bell type furnaces are batch annealing furnaces and are used for heat treatment of both low and high carbon steels. In these furnaces, heat treatment can be carried out under inert gas and vacuum for the protective atmosphere. Such furnaces are widely used in the production of screws and bolts. Pit type ovens are preferred for reaching high charge capacities in heat treatment of smaller 25 - 50 kg coil weights.
· Drying ovens are used in wire coating lines before hot dip operations.