Annealing furnace of conventional construction will cause oil waste, air pollution, thus the furnace will be damaged, affecting the normal production. The main reasons are as following:

     (1) structure is not reasonable. The lining adopts heavy high alumina refractory brick, and hanging off the roof of the structure, and the car door seal is not good, it will cause long time heating, poor insulation, bad heat storage. When the workpiece is heated, much of the heat from the furnace inhaling energy increases, leading to severe heat loss.

     (2) poor sealing. The old equipment’s oven door must be open in order to work properly if the furnace is heated to 600 ℃, causing the flame to break the door and severe heat loss.

     (3) poor combustion conditions. Due to incomplete combustion, when the door closed, it will be easy to plug, so that the furnace increased fuel consumption.

2 rehabilitation programs

     Since the annealing furnace structure can not be changed to a great extent, the choice of high-temperature CCEWOOL alumino silicate refractory ceramic fiber folded block and a new fuel spray combustion technology for system transformation are adopted.

     2.1  removed the original panel and furnace burners on both sides of the shell plate, using A3, S = 30mm, S = 8mm steel, and L100 × L100 × angle iron welded reinforcement.

     2.2 removed the original high alumina refractory bricks lining and use the new energy-saving CCEWOOL alumino silicate refractory ceramic fiber folded block, which is fixed to the furnace wall plus welding folding fibers collapse block with stainless steel fasteners for installation, its performance has anti-oxidation, heat storage, good insulation, heat loss, easy maintenance, energy saving compared with the refractory lining in the 20-30%.

     2.3 Removed the original top heavy high alumina bricks and demolition angle, instead of new energy-saving high-temperature ceramic fiber folding block.

     2.5 reinforced door. Surround the door by L100 × L100 × 10 angle steel reinforcement, installed new energy-efficient furnace door CCEWOOL alumino silicate refractory ceramic fiber collapse block.

     New design, new CCEWOOL refractory materials and new fuel spray combustion technology for heat treatment annealing furnace have been transformed, which completely solve the problem of incomplete combustion, reducing energy consumption, greatly improve the working environment.