With the new-style of lining in conical surface, the pulley change the traditional designing method and convenient to install and disassemble. The pulley has a high precision, and runs credibly. Through using linings of conical surface so it can be used in different installing sizes and occasions. The designing process is simplified escaping the trouble of re-processing, meantime improving the degree of the pulley's general use and standard state. Now it has been used widely in the engine power transmission.