Screw: surface cut with spiral groove cutting with a conical cylindrical or conical spiral groove. The screw has a different head, like the head of the picture is called the outer six angle screw. There are other, such as flat screw, inner six angle screw etc..
Requirements for materials
From the extrusion process, it can be known that the screw is in high temperature, certain corrosion, strong wear, high torque, and therefore, the screw must be:
1) resistant to high temperature, high temperature does not deform;
2) wear resistance, long life;
3) corrosion resistance, corrosion resistance of materials;
4) high strength, can bear large torque, high speed;
5) have good cutting performance;
6) after heat treatment, the residual stress is small, and the thermal deformation is small.
A nut is a fastening member having a drive system and an internal thread, and is designed to be combined with an outer threaded fastener to lock the parts, according to the condition and function of the use and the function in the opposite or shape of a different design and classification. Nut is quick and easy and automated selection have included, common have hexagonal nut, hex flange nut, high strength hex nut, four corners nut, nylon nuts, bag cap nut, combination Huasi nut, Castle groove nut, tire nut, welding nut, connecting nut and so on.
Six nut and screws, bolts, screws are to cooperate with the use of fastening parts. Among them by type 1 six most widely used nuts, C-class nut for rough surface of high precision machinery, equipment or structure; class A and class B nut for surface is smooth, the high precision machinery, equipment or structure. Six type 2 angle nut thickness M thickness, often need to install and dismantle occasions. The thickness of M six angle thin nut is thin, multi connected parts of the surface for space constrained