According to the nature of the force, the spring can be divided intoStretching the spring,Compression spring,Torsion springAnd bending springs, divided by shapeDisc spring,The ring on the spring,Plate spring, helical spring, truncated cone coil spring andThe torsion bar springAnd so on, according to the production process can be divided into cold coil spring and hot coil spring. ordinaryCylindrical springBecause the manufacture is simple, and can be made into various types according to the loading conditions, the structure is simple, so the most widely used. Generally speaking, spring materials should have high elastic limit, fatigue limit, impact toughness and goodHeat treatmentProperties, commonly used carbon spring steel, alloy spring steel, stainless spring steel and copper alloy, nickel alloy and rubber. The spring is made by cold winding and hot winding. The diameter of the spring wire is less than 8 mm, the general use of the cold winding method, greater than 8 mm use the hot winding method. Some springs have to be forced or madeShot blast, can improve the bearing capacity of the spring.