Bell-Type Bright Annealing Furnace

1﹑Application

Bell-type bright annealing furnaces are primarily used for the bright annealing of ferrous and non-ferrous metals, including: ferrous metals such as carbon structural steel, carbon tool steel, spring steel, bearing steel, strip steel, and wire; and non-ferrous metals such as copper, brass, and bronze in the form of strips, coils, and wires.

2﹑Structure

The bell-type bright annealing furnace consists of a heating bell, two furnace bases, two stainless steel inner covers, a cooling cover, and valve rack piping, etc.:
The heating bell is made of steel plates rolled into a circular shape and welded. The upper part of the bell has a lifting point for a crane hook to lift and replace the bell, and the lower part has three support legs for supporting the furnace bell. The bottom is equipped with a sand seal to ensure that the heating bell can be directly pressed onto the flange of the inner cover during heating to achieve a sealing effect. Two guide rings are also provided to allow the heating bell to be easily and accurately placed on the furnace base.
The furnace lining is composed of folded blocks of all-fiber aluminum silicate needled felt and lightweight refractory bricks. This significantly reduces the weight of the bell, improving insulation and reducing energy consumption. The heating elements are resistance strips uniformly suspended around the furnace chamber and fixed with ceramic screws, making them sturdy and durable.
The furnace base is circular in shape and welded from heat-resistant stainless steel plates. Each furnace base has a circular heat-resistant steel bottom plate. Several support tubes are welded below the bottom plate to support the workpiece. A forced convection fan is installed in the center of each furnace base. The motor drives the impeller to achieve forced convection, thus ensuring uniform temperature distribution in the furnace chamber. The fan motor is a water-cooled, sealed, dual-speed motor, allowing for high and low-speed switching. The cooling water ensures that the motor bearings will not be damaged by overheating. A water-cooled rubber sealing ring is installed on the furnace base to seal against the inner cover.