Cold extrusion is characterized by deformation pressure large role in the mold per unit area when the pressure exceeds the cold extrusion deformation 2500-3000MPa/mm2 when the mold is easily worn or damaged, the other hand, if the total distortion force exceeds pressespermissible load, it will damage the press. Squeeze pressure and total deformation force unit for cold extrusion must be calculated in order to provide a basis for the design of cold extrusion die and a cold extrusion equipment.

    Cold extrusion process, the extrusion pressure and it is a constant. Analyzed in front of the cold extrusion the basic principle that the deformation zone of the workpiece is changed, the whole process of extrusion, the extrusion pressure is changed with the changes in the stroke of the press. The cold extrusion stroke relationship can be divided into three stages.

    First stage: Punches downlink, the punch contacts the workpiece to deform metal to fill the mold cavity, since the metal is plastically deformed, and then fill the mold cavity pressure to the workpiece by contact with the workpiece gradually increased, followed by the pressing force increases sharply. When forward extrusion a point is reached, reaches a backward extrusion ', squeezing start resistance to the deformation