Motion of the forging process according to its modes

　　Forgings are deformed in the cold forging process and work-hardened so that the forging die is subjected to high loads. For this reason, high-strength forging dies are required, and a hard lubrication film prevents wear and bonding. In addition, intermediate annealing is required to prevent cracking of the blank to ensure the required deformation capacity. To maintain good lubrication, the blanks can be phosphatized. Since continuous processing of bars and coils is used, it is not yet possible to lubricate the cross-section, so the possibility of using a phosphating lubrication method is being investigated.

　　Forgings can be divided into free forging, cold heading, extrusion, die forging, closed forging, closed forging and so on according to the way of casting billet movement. Both closed forging and closed upsetting have no flying edge and high material utilization. The finishing of complex forgings can be completed by one or several steps. In the absence of fretting, the bearing area of the forging is reduced and the required load is lowered. However, in the case of not being able to completely limit the blank, the blank volume should be strictly controlled, the relative position of the die should be controlled, and the forging should also be checked to minimize the wear of the forging die.

　　Forging process according to its mode of motion is divided into pendulum rolling, pendulum forging, roll forging, wedge cross rolling, rolling ring, rolling and so on. Pendulum rollers, pendulum rotary forgings, rollers can be fine forging. Rolling and cross rolling can be used as a pre-process for slender materials to improve material utilization. The use of free forging and other rotary forging process, can also be localized forming, with a smaller forging size conditions to achieve the forging processing capacity of this forging methods, including free forging, in the processing process, the material away from the die surface is close to the free surface, and thus it is difficult to ensure its accuracy, therefore, the use of computer control of forging die movement direction and rotary forging process, can be obtained in the shape of complex, high-precision products, thereby improving its Processing capacity.

　　When the temperature exceeds 300-400 ° C (steel blue embrittlement zone) 700 ° C - 800 ° C, the resistance to deformation is significantly reduced, and the deformation capacity is significantly increased. Forging according to different temperature zones, for forging quality and forging processing technology requirements, can be divided into cold forging, warm forging, hot forging three molding temperature zone. It turns out that this temperature range is not divided into strict boundaries, in general, in the recrystallization temperature zone of the forging process known as hot forging, and not heated at room temperature forging is called cold forging.

　　Cold forging process, the size of the forgings do not change much. Below 700 ℃ forging process, less oxide formation, no decarburization on the surface. Therefore, as long as the cold forging deformation can reach the energy range, you can get good dimensional accuracy and surface finish. If you control the temperature and lubrication cooling, can be in 700 ℃ temperature forging, in order to obtain higher precision. When hot forging, the deformation energy is small, the deformation resistance is small, and can be forged to process large forgings with complex shapes.