According to the movement mode of billet, forging can be divided into open, upsetting, extruding, die forging, closed die forging, closed-type upsetting forging. For closed-die forging and closed-type upsetting because there is no flying edge, the material utilization is high. It is possible to finish finishing the complex forgings with a process or several processes. As there is no flying edge, the force area of the forgings is reduced and the required load is reduced.
However, it should be noted that the blanks can not be completely restricted, so we should strictly control the volume of the billet, control the relative position of the forging die and measure the forgings to reduce the wear of the forging die.
According to the movement mode of forging die, forging can be divided into rolling, swing forging, roll forging, cross wedge rolling, rolling ring and inclined rolling. Rotary, swing forging and rolling ring can also be used for precision forging process. In order to improve the utilization ratio of materials, roll forging and rolling can be used as the front process of slender materials.
The same as the rotary forging of forging is also a local forming, its advantage is compared with the forging size, less forging force can be achieved in the case of formation. This method of forging, including open forging, expands from the mold surface to the free surface, therefore, it is difficult to guarantee the precision, so the movement direction of the forging die and the spinning process of the computer control, the use of lower forging force can be used to obtain complex shape, high precision products, such as production of many varieties, large size of the turbine blades and other forgings.