According to the mechanical properties, the spring can be divided into tension spring, compression spring, torsion spring and bending spring. According to the shape, it can be divided into disc spring, ring spring, plate spring, spiral spring, truncated cone scroll spring and torsion bar spring. According to the production process, it can be divided into cold coil spring and hot coil spring.
The common cylindrical spring is widely used because of its simple manufacture and simple structure. Generally speaking, spring materials should have high elastic limit, fatigue limit, impact toughness and good heat treatment performance. Carbon spring steel, alloy spring steel, stainless spring steel, copper alloy, nickel alloy and rubber are commonly used. The manufacturing methods of spring include cold coil method and hot coil method.
The diameter of spring wire less than 8 mm is generally cold coiling, and that larger than 8 mm is hot coiling. Some springs need to be pressed or shot peened after being made, which can improve the bearing capacity of springs. [1]