Self-tapping screws have five main features

Self-tapping screwsOrdinary screw use more advanced than some, self-tapping screws without drilling tap holes, with screws and general different, head for the sharp, tooth pitch is relatively large, and a bit like wire tapping without crumbs, can without tapping screws directly into the metal and plastic typically use this method. SaidSelf-tapping screwsMany kinds, but it has the characteristics are the same, there are five main characteristics.

      1, are generally used carburizing steel (99% of total product). Stainless steel or non-ferrous metals can also be manufactured.

      2, the product must be subjected to heat treatment. Carbon steel self-tapping screws must be carburized, stainless steel self-tapping screws must go through solid solution hardening treatment. So that the self-tapping screws to achieve the mechanical properties and performance requirements of the standard.

      3, high surface hardness, good core toughness. That is "just outside the soft inside." This is a self-tapping screw the performance requirements of a major feature. Such as low surface hardness, not screwed into the matrix; as core poor toughness, a twist on the break, can not be used. Therefore, the "just inside the soft outer" is the self-tapping screws to meet performance requirements.

      4, product surface require surface protective treatment, usually plating. Some products subject to phosphate surface treatment (phosphate). Such as: self-tapping screws wallboard mostly phosphide.

      5, cold heading process of production. Recommended high-speed cold heading machine and high-speed or high-speed thread rolling machines planetary thread rolling machine production to ensure product quality. Such production of self-tapping screw head forming a good, high quality thread.