The main features of self-tapping screws

Although there are many types of self-tapping screws, they all have the following main characteristics: (1) Generally, they are made of carburized steel (accounting for 99% of the total products ). It can also be made of stainless steel or non-ferrous metals. (2) The product must undergo heat treatment. Carbon steel self-tapping screws must be carburized, and stainless steel self-tapping screws must be solid solution hardened. In order to make the self-tapping screw meet the mechanical performance and use performance required by the standard. (3) The product has high surface hardness and good core toughness. That is "soft inside and rigid outside". This is a major feature of the performance requirements of self-tapping screws. If the surface hardness is low, it cannot be screwed into the matrix; if the core toughness is poor, it will break when screwed, and it cannot be used. Therefore, "flexible inside and rigid outside" are self-tapping screws that meet the performance req uirements. (4) The surface of the product needs surface protection treatment, generally electroplating treatment. The surface of some products needs to be treated with phosphate (phosphating). For example, self-tapping screws for wall panels are mostly phosphated. (5 ) It is produced by cold heading technology. It is recommended to use high-speed cold heading machine and high-speed thread rolling machine or high-speed planetary thread rolling machine to ensure product quality. The head of the self-tapping screw produced in this way is well formed and the thread quality is high.