The special chassis of the pile driver should have the characteristics of good stability, convenient operation and maintenance, etc., to meet the needs of various construction methods and configurations of the pile driver equipment. The slewing bearing is mostly used to connect the slewing platform and the walking chassis of the crawler pile driver chassis. The application of the slewing bearing on the pile driver is the same as that of the excavator. It acts as a mechanically flexible joint to facilitate their 360 degree rotation.