Spring damping advantages of castor 1, through the height control valve, can make the work of air spring height maintain under any load, also can make the spring under the same load with different heights, therefore, is not conducive to adapt to the environment in the structure of a variety of refuse. 2, air spring has nonlinear characteristics, can according to its characteristic line must be designed to be the ideal curve. 3, air spring stiffness varies with load, thus the natural frequency of vibration under any load constant, the performance of the spring mechanism with almost constant. 3, must according to the stiffness of air spring and with the help of a change for the volume of the air chamber on freedom of choice, and choice of very low. 4, the same air spring, can endure axial and radial load at the same time, also can transfer torque, and through the adjustment of the internal pressure, still can obtain different bearing capacity, thus can adapt many kinds of load must be. 5, and absorb the high frequency vibration and sound insulation performance is good, 6, in the air spring ontology and optional one orifice is set between the air chamber, can play a damping effect, such as aperture freedom of choice, necessary facility shock absorbers. Spring damping properties of castor: suspension wheel structure design is reasonable, the selection of excellent impact resistance aseismic springs, avoid the wheels when a bump on the ground work for damaged by vibration. Adopted the orbital diameter bead plate and base plate, upper plate after carbonitriding heat treatment, can greatly improve the hardness and toughness of bead plate, make bead plate rotating more flexible, easily greatly improve mechanical performance. Adopt high quality high elastic rubber core wheel made of natural rubber, with good toughening elasticity and abrasion resistance. High-tech polyurethane iron core wheel, anti-fouling, oil resistance, abrasion resistance and high load-bearing characteristics.