Gear hydraulic motor
　　Gear motor reversing the structure in order to meet the requirements of equal access to the oil port, with symmetry, there is a separate leakage oil port to the bearing part of the outer shell leads to the leakage of oil; order to reduce the start friction torque, the use of rolling bearings; order to reduce the torque pulsating hydraulic motor gear teeth to be more teeth than the pump. Gear hydraulic motor from the dry seal is poor, less efficient capacity of rent, can not enter the oil pressure is too high, can not produce a greater torque. And the instantaneous speed and torque as the location of mesh points change, so the gear hydraulic motor is only suitable for high-speed small torque applications. Usually dry construction machinery, agricultural machinery and uniformity of torque less demanding on the mechanical equipment.
　　High-speed hydraulic motor
　　The motor rated speed is higher than 500r/min high-speed motor. The basic form of high-speed motor gear, vane and axial piston. They are mainly characterized by a high speed, moment of inertia is small, easy to start, braking, speed and change direction.
　　Low-speed hydraulic motor
　　The hydraulic motor speed is lower than 500r/min hydraulic motors are low speed. Its basic form is a radial piston type. Low speed hydraulic motor main features are: large displacement, large volume, low speed, can be directly connected with the work of agencies, no deceleration device, so that transmission greatly simplified, low-speed hydraulic motor output torque larger, up to several thousand to tens of thousands of Nm, it is also known as the low speed high torque hydraulic motor.