What is the conventional self-tapping screw production process?

stainless steel screws
Is the passivation of stainless steel screws important?
flange bolts
Combination screw screw action

First, screw production process – brushed

It is also known as the extract, and the pump is made to the cold heading machine. There is also a process in front of the bristles that is acid washing, in order to remove the oxide film outside the wire, the surface constitutes a layer of phosphate films, minimizing the outer surface of the wire and the abrasion of the mold. After the wire plate is washed, the wire diameter is required after the tuning machine. Applicable to wires required for large screws, nuts, and self-tapping screws.

Second, screw production process – forming (staple embryo)

For ordinary self-tapping screws, it is first to be headed, generally through the one-scale process. The head forming can be a countersunk head, a round head, a large flat head, an outer hexagon, an inner hexagon, etc.

(1) Blocking: The movable scissors are moved in one direction, and the wires card in the shear is cut into the desired embryo.

(2) A rush: Timming is fixed, and the mold starts the product head to make the next stroke thoroughly. When the product is a word cutting ditch, a strip mold is a concave, an elliptical groove, and the product is a cross groove, and the mold is a concave four-square groove.

(3) Second rush: After one, the flip is all working, the two-stranded mold is moved forward, and the two-strolding is still working forward, and the product is finished. Then the rear rod will be launched.

Self-tapping screw production process

Self-tapping screws

Three, screw production process – rubbing teeth

Generally, the self-tapping screw embryo is threaded, and two tooth plates are required, and a piece of tooth plate is fixed, and the other rolling semi-finished product is moved, and the product is used to make the product plastic deformation, which constitutes the required thread. In addition, if the nut is a wire attack-tapping-to teeth.

Fourth, screw production process – heat treatment

As a screw with hardness requirements, heat treatment (influencing factors) must be, so that the surface hardness and core hardness of the self-tapping screw can achieve a certain amount of requirements, it is not too soft to attack. .

V. Screw production process – surface treatment

The appearance of the exterior is a certain way to form a cover layer in the workpiece appearance. It is intended to be a beautiful, anti-corrosion effect, and the external tables performed are attributed to the following methods: electroplating, hot dip galvanizing , Mechanical plating, etc. Commonly used electroplating has galvanized, black / white nickel, black, phosphating, etc.

Finally, after the five steps were completed, the self-tapping screw finished product, of course, the screening and drying of the defective product were also available.