Self -tapping screw is a screw with drill bit. It is constructed through a dedicated electric tool. Drilling, tapping wire, fixing, locking is completed once. The general screw must have a processed threaded hole to screw in.

Self -tapping screw structure

Each Self -tapping screw is composed of three parts: head, pole, and the end of the rod. Each Self -tapping screw composition has four major elements: head shape, wound method, thread type, and end form.

1 Head shapes of self tapping screws

The head shape is all kinds. There are round heads (semi -round heads), flat round head, round head convex (with pads), flat round head convex margin (with pads), plate head, plate head convex edge (with pad), auxiliary head, semi -obsculed head, semi -obsculed head, half -imcaded head, semi -obsculed head, semi -obsculed head, semi -obsculed head, semi -obsculed head, semi -obsculed head, semi -obsculed head, semi -obsculed head, semi -obe: Cascane heads, spherical balls, horn heads, hexagonal heads, hexagonal Frank heads, hexagonal bumps (with pads).

2 Driving methods of self tapping screws

The method of wiring refers to the method of twisting the screw head when installing and fastening screws. The basic ways include two types: externally wiping and inside wiping. Generally speaking, the torque allowed by the outer wiping is larger than the inner torque (inner groove). External tips: hexagonal, hexagonal flange noodles, hexagonal bumps, hexagonal flowers, etc.; Inner tips: one -word groove, cross groove H -shaped, cross groove Z, cross slot F, square slot, composite slot, inner flower, flowers, flowers, inner flowers, inner flowers, inner flowers, inner flowers Bonds, inner hexagonal flowers, inner triangles, inner hexagonal, inner 12 corners, clutch grooves, hexagonal grooves, high -torque cross grooves, etc.

3 Thread types of self tapping screws

There are many types of threads, including Self -tapping thread (wide tooth thread), machine thread (ordinary thread), dry wall nail threads, fiber plate threads, and other special threads. In addition, threads can be divided into single -guide (single head), double -headed (double head), multi -guide (multi -head), and high and low teeth double -headed threads.

4 End form of self tapping screws

There are two types of end forms: cone end and peace end. However, according to the needs of the use, at the end of the end, it can be processed with a part with cutting functions, grooves, incisions, or similar drills. In some standards, there are also cone end or flat ends, and there are different forms such as round heads.

Types of Self -tapping screw 

According to the development and evolution of Self -tapping screws, we believe that the types of Self -tapping screws are mainly the following:

01 Ordinary Self -tapping screws

The thread is “Self -tapping thread”, also known as “wide tooth thread”. The surface is mostly electroplating.

02 Cut Self -tapping screw

China’s standards are called “Self -tapping screw scraping end”. The thread is a Self -tapping thread or machine thread, and the cross groove is also “H” type. There are several types of self -cutting screws: the cross head head of the cross, the Self -tapping screw, the cross -headed head of the cross -cut Self -tapping screw. The cross semi -staple head is Self -tapping screws, and the hexagonal head is self -cut.

03 Self -squeezed Self -tapping screw (Self -tapping lock screw)

Self -squeezed screws are generally machine threads and rarely use Self -tapping threads. In the wound method, in order to ensure the use of the wrench high -speed automatic assembly, slots are generally not recommended. The screw cross section of the self -squeezed screw is tritenules. So it is also called the triangular thread screw.

04 Drilling Self -tapping Screw (self -drilling screw)

Self -tapping screw threads, China, Germany and international standards are Self -tapping threads. The BSD Self -tapping screw in the American and SAE standards is the Self -tapping thread, and the CSD self -drill Self -tapping screw is a machine thread. Self -drilling screws are not recommended to use “slot” and “ordinary hexagonal heads”.

05 Metal drive screw (metal strong tapping screw)

The screws of the metal -driven screws are long and have a special thread with a certain spiral angle. Only metal -driven screws in the US standards, my country and German standards are not available.

06 Wallboard Self -tapping screw (dry wall nail)

The white -tapping screws of the wall plate are housing, cross grooves (H -shaped), and special threads with 60 ° tooth angles, and the surface is mostly phosphate treatment (phosphorusization).

07 Chipboard screws

The cross slot is Z, and the surface treatment is mostly electroplated. The fiber plate nails have the following types of several types: the fibrous plate nails of the dwelling head, the double -headed head, the plate, the plate head convex (with the pad) fiber plate nail, the semi -imperial head, the half -deep head bump (with the pad) fiber plate nail.

08 Comb Self -tapping screw

Ordinary white -tapping screws, self -cut white tapping screws manufacturers, self -drilling Self -tapping screws, such as a combination of Self -tapping screws made of flat pads, elastic pads (including spring pads, elastic locking cushioning Type T.

09 Other Self -tapping screw types

Self -tapping screws of high and low teeth, thick, fine teeth (different thread spacing) snail Self -tapping screws, threaded Self -tapping screws with sealing materials (resistant), various composite slot Self -tapping screws, other special juice juice Self -tapping screws, etc.

In short, there are many types of Self -tapping screws. With the development of production and the advancement of technology, new materials, new structures, and new thread forms, new Self -tapping screw products will continue to appear.

Self -tapping screw characteristics

① Self -tapping screw is a screw with a drill head. The inner hexagonal bolt is constructed through a dedicated electric tool. Drilling, tapping wire, fixation, and locking are completed once. Self -tapping screws are mainly used for the connection and fixing of thin sheet parts, such as the connection between color steel plates and color steel plates, the connection between color steel plates and bars, wall beams, etc. Its penetration ability generally does not exceed 6mm, and the maximum does not exceed 12mm.

② Self -tapping screws are often exposed to the outdoor, and it has a strong corrosion resistance; its rubber sealing ring can ensure that the screws are not seepage and have good corrosion resistance.

③ Self -tapping screws are suitable for wooden materials, which are the wood screws we often call. Generally, it is manual operation. Due to human limitation, this screw is generally small and the range of use is relatively narrow.

④ Self -tapping screws are combined with taps and bolts. The front is a tap and a thread behind. On the general soft materials, drill one empty can be screwed in directly. The thread was tappinged by the tap, and then the bolt thread was vigorous. If the screw diameter is small, the material is also very soft. You don’t need to pinch it first, such as screwing into the wood.

⑤ Self -tapping screws are generally described with three parameters: screw diameter level, number of screws per inch length, and screw length. There are two types of screw diameter level 10 and level 12, and the corresponding screw diameter is 4.87mm and 5.43mm. The number of screws per inch is 14, 16, and 24. The stronger the drilling ability.