Pulleys, which belong to the disc hub parts, are generally relatively large in size, and the manufacturing process is generally based on casting and forging. Generally, the design of larger size is the method of casting, and the material is generally cast iron (good casting performance), and rarely cast steel (the casting performance of steel is not good); Generally, the size is smaller, and it can be designed for forging, and the material is steel. Pulleys are mainly used for long-distance transmission of power occasions, such as the output of small diesel engine power, agricultural vehicles, tractors, automobiles, mining machinery, mechanical processing equipment, textile machinery, packaging machinery, lathes, forging machines, transmission of some small horsepower motorcycle power, transmission of agricultural machinery power, air compressor, reducer, reducer, generator, ginning machine and so on.