The process of producing each product needs to pay attention to some important points. During the process of forging pulleys, special attention should be paid to these matters, so as to minimize product misunderstandings and ensure the quality of forgings. Let's take a look at the precautions for forging pulleys in the forging process.
1. When forging pulleys, light pressure is required at the very beginning, and the weight can be increased only after the deformation reaches 30%. When forging, they should be fed in one direction to avoid repeated presses in one place to prevent the occurrence of a central cross crack.
2. The forging ratio of steel ingots for forged pulleys is 4 to 6, and the steel billets are 2 to 4, depending on the grain size of the raw materials. The grain size has a great influence on the corrosion resistance of the steel. In order to obtain fine grains and fully weld the micro cracks and pores in the center zone, it is necessary to ensure that the final fire has a large enough forging ratio, and the deformation amount should be greater than the critical degree of recrystallization, and the deformation amount should generally be greater than 12% to 20%.
3. Deformation process requires uniform deformation to obtain a more uniform grain structure.
Forged pulley manufacturing method
1. Use a smooth platform and anvil surface, if necessary, lubrication.
2. Preheat the platform and anvil surface to 150~450°C.
3. Both ends of the billet are filled with low carbon steel pads.
4. Using stacked forging.
5. Use intermittent compression when deforming.
6. Wrap up rough.
When the forged pulleys are finally formed, a large shrinkage (1.5~1.7%) should be taken into consideration to avoid wastes due to insufficient size after the forgings are cooled. Forging temperature should be more than 850 °C trimming (cold forgings should be preheated to 900 ~ 950 °C then trimming).