The air spring has the characteristics of light weight, strong steering stability, wear-free pneumatic damping, stable working height, perfect lifting function, long service life, good vibration isolation, sound insulation, small installation space and convenient replacement. However, the air spring also has the disadvantage that it can only bear vertical loads, and a guiding mechanism is required to transmit longitudinal force, lateral force and its moment, resulting in a relatively complicated suspension structure.

According to the sealing type, air springs are divided into four types: steel ring crimping type, one end crimping type, both ends crimping type and self-sealing type. The air spring is mainly loaded by the middle 2 layers of cords. In special cases, single-layer cords can also be used. The inner layer of rubber mainly plays the role of sealing, and the outer layer of rubber plays the role of sealing and surface protection.