In the fastener forming process, cold heading (extrusion) technology is a main processing technology, which belongs to the category of metal pressure processing. In production, at room temperature, external force is applied to the metal to form the metal in a predetermined mold. This method is usually called cold heading. In fact, the forming of any fastener is not only achieved by cold heading. In the cold heading process, in addition to upsetting deformation, it is also accompanied by positive and negative extrusion, compound extrusion, punching, rolling and other deformation methods. Therefore, the name of cold heading in production is just a habitual name. To be more precise, it should be called cold heading (extrusion).

Cold heading (extrusion) has many advantages, and it is suitable for mass production of fasteners. Its advantages can be summarized as follows:
1. High steel utilization rate. Cold heading (extrusion) is a method with little or no cutting. For example, when processing hexagonal bolts and cylindrical socket screws of rods, the steel utilization rate is only 25% to 35% by cutting, while the utilization rate can be as high as 85% to 95% by cold heading (extrusion), which is only some process consumption of the head, tail and hexagonal head edge.
High productivity. Compared with general cutting, the efficiency of cold heading (extrusion) is more than dozens of times higher.
2. Good mechanical properties. The strength of parts processed by cold heading (extrusion) method is much better than that of cutting because the metal fibers are not cut.
3. Suitable for automated production. Fasteners (including some special-shaped parts) suitable for cold heading (extrusion) method are basically symmetrical parts, suitable for production by high-speed automatic cold heading machine, and are also the main method of mass production.
In short, the cold heading (extrusion) method for processing fasteners and special-shaped parts is a processing method with a relatively high comprehensive economic benefit. It is a processing method commonly used in the fastener industry. It is also an advanced processing method that is widely used and developed at home and abroad.

At room temperature, the blank is placed in the mold of an automatic cold heading machine or a press, and pressure is applied to the mold. The relative movement of the upper and lower molds is used to deform the blank in the mold cavity, reduce the height, and increase the cross-section. This pressure processing method is called cold heading for automatic cold heading machines and cold pressing for presses. In actual production, the cold forming process of fasteners is often accompanied by extrusion during the cold heading process. Therefore, the cold heading process of fastener products alone is actually a composite processing method that has both cold heading and extrusion.