There are mainly two types of ball pin structures: one is the combination of ball pin and integral ball seat, and the other is the combination of hemispherical ball pin and spherical component. The material and shape of the dust cover and the type of grease have been greatly improved, and the grease nozzle has been canceled to realize the maintenance free structure.

The ball pin is mainly composed of end cap, ball pin, ball seat and dust cover, as shown in the figure. The end cover is mostly made of steel plate stampings, mainly made of carbon steel, and some are made of aluminum alloy or ductile iron.

The machining accuracy of the ball pin surface is required to be high. Alloy steel with good hardenability is mostly used. The surface of the ball pin matched with the metal ball needs to be hardened by high-frequency quenching and other surface hardening treatment to improve the wear resistance. Now, ball pins are mostly used to fit with non-metallic ball seats, so only the ball pins need to be quenched and tempered. The diameter of ball pin shall be selected according to tensile strength, durability and other factors

heaterials of the ball seat are surface hardened steel, powder metallurgy, nylon, polyacetal resin, polyurethane and polyester elastomer. Since the material and shape of the ball seat have a great influence on wear and fatigue life, the material is immersed in molybdenum disulfide or oil to improve wear resistance. Stiffeners or composite materials can also be added on the ball socket.

The tightness of the dust cover has a great influence on the wear and fatigue life of the ball pin. Its materials are mostly polyurethane or neoprene with high temperature resistance, oil resistance and aging resistance. In addition, the deformation during movement shall be considered in the design to prevent dust from entering the ball pin from the mating surface after deformation. At the same time, the matching accuracy of the dust cover and related parts also has a great impact on the tightness and service life.