Technology control in the bright quench process with the mesh-belt furnace

Mesh-belt furnace is a continuous heat treatment device widely used in the bright quench for the small articles with large pitch. The state parameters determining the heat treatment quality can not be controlled directly in the mesh-belt furnace for the 2 reasons. The first is that the furnace is sealed with the fire tone. The other is that the articles move with the mesh-belt all the time in the heating process. The state parameters, which decide heat treatment quality, cannot be directly controlled in the mesh-belt furnace. Moreover, these parameters have no simple relationship with the technological variables, which can be directly adjusted. By this reseason, it is dificult to fulfil the heat treatment purpose in the mesh-belt furnace by the operator’s experience. It is proposed in this paper to controll heating process according to the state parameters. This method was aplied to the technoloy optimization in the needle poduction. The needle duration increases about 1 time by the improved technology.