Forged pulleys need to be comprehensively considered in the forging process, so as to minimize the misunderstanding of the products and ensure the quality of the forgings. First, when the pulley is forged, light pressure is started, and when the deformation amount reaches 30%, it can be pressed. When forging, it should be fed in one direction to avoid repeated pressing at one place to prevent center cross cracks.
Secondly, it is necessary to determine the suitable process according to the characteristics of the material selected for the forged pulley. For example, in order to obtain fine grains and fully weld the micro-cracks and pores in the central region, it is necessary to ensure that the last fire has a sufficiently large forging ratio, and the deformation amount should be More than the critical degree of recrystallization, the deformation should generally be greater than 12% to 20%.
It should be noted that in the deformation process of the forged pulley, it is necessary to ensure uniform deformation, which is mainly to obtain a uniform grain structure. Moreover, when the forging is finally formed, a large shrinkage ratio (1.5 to 1.7%) should be considered to prevent the forging from being scrapped due to insufficient size after cooling. Generally, the forging temperature should be controlled at 850 °C or more (the cold forgings should be preheated to 900~950 °C and then cut).