Hot forging means forging blank metal above the recrystallization temperature carried out. Features: reducing the deformation resistance of metals, thus reducing bad forging force needed to deform the material, so that greatly reduced the tonnage forging equipment; altering the structure of ingots cast in forging process after recrystallization becomes coarse cast structure the new organization of small grains, and reduce defects in the cast structure to improve the mechanical properties of steel; improvingthe ductility is difficult for some of the more brittle at low temperatures in high alloy steel forging, which is important. Applicable large deformation resistance at room temperature, a poor metal plastic material. Hot metal forging temperature range refers to the temperature and the temperature began to forge some interval between the end of the forging temperature, in order to prevent overheating, burning need to correctly determine the initial forging temperature and the final forging temperature. The basic approach is to develop the heating temperature of the iron-carbon equilibrium pictured steel base. 

Cold forging is below the recrystallization temperature of the material forming, forging is carried out at a temperature below the reply. Production accustomed to rough unheated be called cold forging forging. Under cold forging temperature deformation resistance of the material are mostly small, plastic and some aluminum alloys better, and some copper alloy, low carbon steel, carbon steel, low alloy steel. Cold forging good surface quality, high dimensional accuracy, can replace some of the cutting. Cold forging metal can strengthen and improve the strength of the parts. Cold forging technology is to be higher than the temperature of the forming precision forging and forging, precision forming field has its unique advantages. Cold forging process using improved bore finish, dimensional accuracy, surface strength, prolong the life of the barrel, shooting accuracy that a corresponding increase in the gun, and ease of machining tapered barrel, the quality can be reduced.