Self tapping screw function

Self-tapping screw is a screw with a drill, through the construction of special power tools, drilling, tapping, fixing, locking once completed. Self-tapping screw is mainly used for the connection and fixation of some thin plates, such as the connection between color steel plate and color steel plate, and the connection between color steel plate and purline, wall beam, etc., its penetration capacity is generally not more than 6mm, the maximum is not more than 12mm. Self-tapping screws are often exposed to the outside world and have strong corrosion resistance. Its rubber sealing ring can ensure that the screw is impermeable and has good corrosion resistance.

Self-tapping screws are usually described in terms of the diameter of the screw, the number of threads per inch of length, and the length of the screw. There are two types of screw diameter series: 10 and 12, and the corresponding screw diameters are 4.87mm and 5.43mm, respectively. There are 14, 16 and 24 grades of threads per inch. The more threads per inch, the more self-drilling capability.

Self tapping screw HAW hexagon self tapping screw, stainless steel self tapping screw, galvanized self tapping screw and so on

Although there are many types of self-tapping screws, they all have the following main characteristics:

(1) are generally made of carburized carbon steel (accounting for 99% of the total product). It can also be made of stainless steel or non-ferrous metal.

(2) the product must undergo heat treatment. Carbon steel self - tapping screws must undergo carburizing treatment, stainless steel self - tapping screws must undergo solid solution hardening treatment. To make the tapping screw to meet the standard mechanical and service performance.

(3) high surface hardness and good core toughness. That is, "internal softness and external stiffness". This is a major feature of self - tapping screw performance requirements. If the surface hardness is low, screw into the matrix; If the core toughness is poor, a twist broken, also can not be used. Therefore, "internal softness and external stiffness" are self-tapping screws to meet the requirements of the performance.

(4) all the surfaces of the products need surface protection treatment, generally electroplating. Some product surfaces require phosphate treatment (phosphating). Such as: wall board since tapping screws for phosphating.

(5) use cold heading process. It is recommended to use high speed cold heading machine and high speed spinning machine or high speed planetary rolling machine to ensure product quality. In this way, the tapping screw head is well formed and the thread quality is high.