Solid Brass Metric Hexagon Head Bolts Fully Thread Screws M4 M6 M8

A bolt is a mechanical part, a fastener, a cylindrical threaded fastener equipped with a nut. It consists of two parts: the head and the screw (a cylinder with external threads), which needs to be used in conjunction with a nut to fasten two parts with through holes. This form of connection is called a bolt connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.

There are many types of bolts that can be classified according to different criteria. According to the force-bearing method of the connection, bolts can be divided into ordinary and reamed holes. According to the shape of the head, there are hexagonal head, round head, square head, countersunk head, etc. Among them, the hexagonal head is the most commonly used. Generally, countersunk heads are used where connections are required. In addition, there are many special types of bolts such as saddle bolts, anchor bolts, shoulder bolts, tapered head bolts, etc., which have special functions and uses in specific applications.

The performance grade of a bolt is also one of its important characteristics. The performance grades of bolts used for steel structure connections are divided into multiple grades such as 3.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, and 12.9. Among them, bolts of grade 8.8 and above are made of low-carbon alloy steel or medium-carbon steel and have been heat treated (quenching + tempering). They are commonly called high-strength bolts, and the rest are commonly known as ordinary bolts. The meaning of bolt performance grade is an internationally accepted standard. Bolts with the same performance grade have the same performance regardless of differences in materials and origins. Only the performance grade can be selected for design.

With the development of science and technology and the progress of materials engineering, the production technology of bolts has been continuously improved, and new stainless steel materials have also been applied to the manufacturing of bolts to improve their corrosion resistance and strength to meet the needs of use in different environments. In the future, as industrial production continues to deepen, the manufacturing process of bolts will become more automated and intelligent, and production efficiency and product quality will be improved. At the same time, relevant standards and inspection methods will be further improved to ensure product quality and safety.