SCREW

Screw is a tool that utilizes the physical and mathematical principles of the object's inclined plane circular rotation and friction to gradually tighten the device. Drill-tail screws can also be called drill-tail self-tapping self-drilling screws, drill-tail screws, self-drilling screws, and dovetail screws. The tail of the drill-tail screw is in the shape of a drill tail or a pointed tail. It can be directly set on the material and foundation without auxiliary processing. Drilling, tapping and locking materials can greatly save construction time. Compared with ordinary screws, its tough pull-out force and high retention force will not loosen for a long time and are safe to use. Especially in the combination of construction, construction, residential and other places, self-tapping self-drilling screws are the best economical fasteners in terms of workability, cost and reliability. Drill tail screws are screws with a self-tapping drill bit at the front end of the screw.

The tail of the drill tail screw is in the shape of a drill tail or a pointed tail. No auxiliary processing is required. Drilling, tapping and locking can be directly performed on the installation materials and basic materials, greatly saving construction time. Compared with ordinary screws, they have higher toughness and retention force, and will not loosen for a long time after being assembled. It is easy to use safe drilling and tapping to complete the operation in one go.

Drill tail screws: They are mainly used for fixing colored tiles in steel structures. They can also be used for fixing thin plates in simple buildings, but they cannot be used for fixing metals and metals.

There are two types of materials: iron and stainless steel. Stainless steel is divided into multiple materials.

Models include: Φ4.2/ Φ4.8/ Φ5.5/ Φ6.3mm, the specific length can be negotiated according to requirements.

According to the different drill tails, it can be divided into:

Round head rice/cross/plum blossom, countersunk head (flat head)/rice/cross/plum blossom, hexagonal washer, round head washer (large flat head), trumpet head, etc.

1. Cross recessed pan head self-tapping self-drilling screws, also known as round head drill tail.

2. Cross recessed countersunk head self-tapping self-drilling screws, also known as flat head drill tail.

3. External hexagonal tapping self-drilling screw, also known as hexagonal Dahua drill tail.

4. External hexagonal flange self-tapping self-drilling screw, also known as hexagonal drill tail.

5. Cross recessed semi-countersunk head self-tapping drill screws, but this head type is less commonly used.

Compared with ordinary screws, drill tail screws have higher toughness and maintainability. They will not loosen even after being assembled for a long time. Drilling and tapping can be completed safely and easily in one operation.

1) Cross recessed pan head self-drilling and tapping screws: Implementation standard: GB/T 15856.1-2002, also known as round head drill tail.

2) Cross recessed countersunk head self-drilling and tapping screws: Implementation standard: GB/T 15856.2-2002, also known as flat head drill tail and salad head drill tail.

3) Cross-recessed countersunk head self-drilling and tapping screws: Implementation standard: GB/T 15856.3-2002. The semi-countersunk head is rarely used in the market.

Hexagonal flange surface self-drilling and tapping screws: Implementation standard: GB/T 15856.4-2002, also known as hexagonal Dahua drill tail, which is the most commonly used and largest specification among drill tail screws.

Hexagonal flange self-drilling and tapping screws: Implementation standard: GB/T 15856.5-2002, also known as hexagonal Xiaohua drill tail.

According to the material, it can be divided into steel 1022A, stainless iron 410, and stainless steel 304.

Carbon steel drill screws: 1022A. Standard heat-treated steel can be used as a material for the production of drill screws. The surface hardness after heat treatment is HV560-750, and its core hardness is HV240-450. Ordinary surface treatment is easy to rust, has high hardness and is low in cost. .

Stainless steel drill tail screws: 410 can be heat treated, and its anti-rust ability is better than carbon steel but worse than stainless steel.

Stainless steel drill tail screws: 304 cannot be heat treated, has strong anti-rust ability, low hardness, and high cost. It can only drill aluminum plates, wooden boards, and rubber plates.

Composite drill tail screw: The drill bit is produced by a combination of carbon steel thread production and 304 stainless steel head.