In the fastener forming process, the cold heading (extrusion) technology of the screw cold heading machine is a major processing process. Cold heading (extrusion) belongs to the category of metal pressure processing. In production, at room temperature, an external force is applied to the metal to form the metal in a predetermined mold, which is usually called cold heading.
In fact, the forming of any fastener is not only a deformation method of cold heading, but also accompanied by a variety of deformation methods such as forward and reverse extrusion, compound extrusion, punching and cutting, rolling and other deformation methods in the cold heading process. Therefore, the name of cold heading in the production of screw cold heading machine is just a habitual name, more precisely, it should be called cold heading (extrusion) Cold heading (extrusion) has many advantages, and it is suitable for mass production of fasteners.
a. High utilization rate of steel. Cold heading (extrusion) is a few, no cutting processing method, such as processing rod hexagonal head bolts, cylindrical head hexagon screws, using cutting processing methods, the steel utilization rate is only 25% ~ 35%, and with cold heading (extrusion) method, its utilization rate can be as high as 85% ~ 95%, only some process consumption of material head, material tail and cutting hexagonal head edge.
b. High productivity. Compared with general cutting processing, the efficiency of cold heading (extrusion) forming is more than ten times higher.
c. Good mechanical properties. The strength of the parts processed by the cold heading (extrusion) method is much superior to that of cutting because the metal fibers are not cut.
d. Suitable for automated production. Fasteners (including some special-shaped parts) suitable for cold heading (extrusion) production are basically symmetrical parts, suitable for high-speed automatic cold heading machine production, and are also the main method of mass production.
