Cold heading and hot heading in bolts fasteners

Bolt, High strength bolts, Screw

Cold head refers to the use of the plasticity of metals and the use of cold mechanics for pressure or cold drawing to achieve the goal of solid deformation of metals. On the surface, cold headed products look more beautiful and have a better finish than hot headed products. In terms of use, the hardness of hot headed nuts is generally higher than that of cold headed products, with higher strength. For demanding users, there are significant differences in materials.



The forging method of thickening the top of a bar or wire at room temperature. Cold head is mainly used for manufacturing parts such as bolts, nuts, nails, rivets, steel balls, etc. The forging billet material can be copper, aluminum, carbon steel, alloy steel, stainless steel, titanium alloy, etc., and the material utilization rate can reach 80-90%. Cold heading is often carried out on specialized cold heading machines, facilitating continuous, multi-station, and automated production. The cold head machine can sequentially complete processes such as cutting, cold head, accumulation, forming, chamfering, wire rolling, diameter reduction, and edge cutting. High production efficiency, up to 300 pieces/minute or more, with a maximum cold head diameter of 48mm.



The schematic diagram of cold head bolt process is a typical process for cold head bolts. The multi-station nut automatic cold heading machine is a multi-station nut automatic cold heading machine. The bar is automatically fed into a certain length by the feeding mechanism, cut into blanks by the cutting mechanism, and then sent to the accumulation and punching station by the fixture conveying mechanism to form.