Self-tapping screw, the English name Self-tapping Screw, is a kind of threaded fastener that is self-tapping in the pre-drilled hole of metal or non-metal material.
Because it is self-forming or can tap the thread that matches it, it has high anti-loose ability in combination and can be loaded and unloaded. In the small screw, its size, thread type, head type, tapping performance, high tensile force for engineering purposes, single piece, single side combination features are limitless. Self-tapping materials can be divided into carbon steel and stainless steel, of which carbon steel is mainly composed of 1022 medium carbon steel. Usually used on doors and windows, iron sheets. The head is a bearing surface formed by forming a portion having an increased shape at one end. For tapping and thread cutting self-tapping screws (self-tapping screws), FlatCountersunk, Oval Countersunk, Pan, Hex and Hex Wash Head The most important, these five types of heads account for almost 90% of all self-tapping screws, the use of self-tapping screws (self-tapping screws) should be considered first. The other five other types are Flat Undercut, Flat Trim, Oval Undercut, Oval Trim and Cylindrical Head (Fillister) In order to compare the secondary head shape, the top of the incense stick is buried. The choice of the thread rolling into the self-tapping screw (self-tapping screw) is the same as the above. The main consideration is the Truss, Round and 100 degrees. The top buried head is not taken for the new design. The function of the top can be replaced by other head types. The pan head can replace the mushroom head and the round head. The 82 degree flat top can replace the 100 degree flat top, flat dome and pan head. Five kinds of hexagonal heads and hexagonal heads.