Screw Suppliers

Expansion Of Relevant Industry Knowledge
A screw is a type of fastener, usually made of metal, that can be used to connect, secure, or assemble various parts and structures. There are various types of screws, which can be divided into round head screws, countersunk head screws, half round head screws, etc. based on their head shape; According to its tail shape, it can be divided into straight thread screws, self tapping screws, drill tail screws, etc. There are also various materials for screws, including carbon steel, stainless steel, copper, aluminum, etc. The specifications and dimensions of screws are usually determined by factors such as their diameter, length, and head shape. When using them, it is necessary to choose the appropriate screw according to the specific situation and requirements.

What does screw's head look like?
The head of a screw comes in various shapes and designs, and each type serves a specific purpose. Here are some common types of screw heads:
1.Flat Head (Countersunk): This head is flat on the top and is designed to sit flush with the surface of the material. It's often used when a smooth finish is desired.
2.Round Head: This head is semi-circular and protrudes above the surface of the material. It provides a good bearing surface and is often used in applications where a stronger joint is required.
3.Pan Head: Similar to a flat head but with a rounded top, a pan head is slightly raised above the surface. It offers a good compromise between a flat head and a round head.
4.Truss Head: This head has a wider surface area and a lower profile compared to a pan head. It provides more support and is often used in applications where a larger load-bearing surface is required.
5.Oval Head: The oval head is similar to a flat head but with a slightly rounded top. It combines some of the benefits of flat and round heads.
6.Hex Head (Hexagonal): Instead of a traditional screwdriver slot, hex head screws have a hexagonal shape, requiring a corresponding hex wrench or Allen key for installation.
7.Phillips Head: The Phillips head has a cross-shaped recess, requiring a Phillips screwdriver for installation. It is designed to provide better torque transfer and reduce cam-out (slipping) compared to a simple slot.
8.Torx Head: Torx screws have a star-shaped recess, requiring a Torx screwdriver or bit for installation. This design offers increased torque transfer and helps prevent cam-out.
9.Square Head: Square head screws have a square-shaped recess and are driven using a square bit. They are less common but offer good torque transfer.
10.Socket Head (Internal Hex): These screws have a cylindrical head with a hexagonal recess. They are often used in machine and assembly applications.

What are the thread directions of screw?
The thread direction of screws is divided into two types: left-hand and right-hand. The spiral of a left-hand thread slopes downwards to the right, usually used for fixing and removing screws, while the spiral of a right-hand thread slopes upwards to the right, usually used for transmitting power and changing the form of motion. In addition, there are some special thread directions, such as straight lines, which are a type of thread without an inclination angle and are usually used for fixing and sealing purposes. Overall, the thread direction of a screw depends on its specific purpose and function.