The types of cold extrusion molding are as follows:

1. Positive extrusion

During forward extrusion, the flow direction of the metal is consistent with the movement direction of the punch. Forward extrusion can produce solid and hollow parts of various shapes.

2. Back extrusion

During back extrusion, the flow direction of the metal is opposite to the movement direction of the punch. Reverse extrusion can obtain cup-shaped pieces of various shapes.

3. Compound extrusion

During extrusion, part of the blank metal flows in the same direction as the punch, while another part of the metal flows in the opposite direction to the punch. Compound extrusion can produce various cups, rods, and barrel parts.

4. Radial extrusion

During extrusion, the flow direction of the metal is perpendicular to the movement direction of the punch. Radial extrusion can be divided into centrifugal extrusion and centrifugal extrusion. Radial extrusion is used to make parts such as helical gears and flower keyboards.

5. Forging

During forging, the metal blank flows radially outward. Upsetting is used to manufacture flanged shaft parts or flanged cup-shaped parts.

Forward extrusion, reverse extrusion and compound extrusion are the three most widely used methods in cold extrusion technology. Their metal flow direction is parallel to the axis of the punch. Therefore, many materials also call these three methods as axial extrusion. As mentioned earlier, various solid and hollow parts can be produced by axial extrusion, such as ball pins, bobbin shells, and bullet shells. Radial extrusion has only been developed in the past ten years, and is mainly used for dials of communication equipment and flower keyboards of bicycles.

The above are several basic cold extrusion deformation methods. With the development of cold extrusion technology, cold bulk die forging is sometimes classified as cold extrusion. Cold extrusion is widely used in electromechanical manufacturing such as automobiles, tractors, bearings, telecommunications equipment, meters, bicycles, sewing machines, and other light industries, as well as in defense industry systems. This is because it has obvious advantages.