What is the difference between a cold head nut and a hot head nut?

Cold sputum: It is the use of metal plasticity, cold pressure mechanics for pressure or cold drawing, to achieve the purpose of solid metal deformation. A method of forging the top of a bar or wire at room temperature. Cold heading is mainly used to make parts such as bolts, nuts, nails, rivets and steel balls. The forging material can be copper, aluminum, carbon steel, alloy steel, stainless steel and titanium alloy, and the material utilization rate can reach 80-90%. Cold heading is carried out on a dedicated cold heading machine, which is convenient for continuous, multi-station and automated production. In the cold heading machine, the processes of cutting, hoeing, accumulation, forming, chamfering, twisting, shrinking and trimming can be sequentially performed.