Crawler bulldozers adopt mechanical transmission or hydraulic mechanical transmission system with hydraulic torque converter, and a few adopt hydraulic transmission system. The pump wheel in the pump wheel assembly is connected with the drive housing by bolts, and the drive gear is connected with the drive housing by bolts. The drive gear is directly inserted into the flywheel ring gear of the engine, so the pump wheel rotates with the engine. The guide wheel is connected with the guide wheel hub by bolts, the guide wheel hub is connected with the guide wheel base through splines, and the guide wheel base is connected to the torque converter housing by bolts, so the guide wheel and the torque converter housing together do not rotate.
The turbine and the turbine hub are riveted together with rivets, and then connected to the turbine output shaft through a spline, and the turbine output shaft is connected through a spline and a coupling to transmit power to the subsequent transmission system. The pump wheel rotates with the engine to input power, the guide wheel does not rotate, and the turbine rotates to output power. The three are independent of each other, and the gap between the wheels is about 2mm.
