Hydraulic pumps and hydraulic motors are essential hydraulic components for each excavator, and their construction and working principle are very similar.


Similarities between hydraulic motors and hydraulic pumps:

1.In principle, hydraulic motors and hydraulic pumps are reversible. If the motor is driven, the output is hydraulic energy (pressure and flow), is the hydraulic pump; if pressure oil is input, the output is mechanical energy. Torque and speed) become hydraulic motors.

2.From a structural point of view, the two are similar.

3.In terms of working principle, both use the change of the sealed working volume to suck and drain oil. For the hydraulic pump, the oil is sucked when the working volume is increased, and the high pressure oil is discharged when the working volume is decreased. For the hydraulic motor, the high pressure oil is entered when the working volume is increased, and the low pressure oil is discharged when the working volume is decreased.

The difference between hydraulic motor and hydraulic pump:

1.The hydraulic main pump is an energy device and the hydraulic motor is an actuator. A hydraulic pump is a conversion device that converts the mechanical energy of a motor into hydraulic energy. Output flow and pressure are expected to be high in terms of volumetric efficiency. The hydraulic motor is a device that converts the pressure energy of the liquid into mechanical energy, outputs torque and speed, and has high mechanical efficiency.

2.The steering of the output shaft of the hydraulic motor must be able to rotate back and forth, so its structure is symmetrical; some hydraulic pumps (such as gear pumps, vane pumps, etc.) have clear steering regulations, can only be rotated in one direction, and cannot change the direction of rotation at will.

3.In addition to import and export, the hydraulic motor also has a separate drain port. The hydraulic pump generally only has an inlet and outlet (except for the axial piston pump), and the internal drain is connected to the inlet and outlet.

4.The hydraulic motor volumetric efficiency is lower than the hydraulic pump volumetric efficiency.

5.The working speed of the hydraulic pump is generally high, and the output speed of the hydraulic motor is low. In addition, the gear pump has a large oil inlet and a small oil outlet, and the gear hydraulic motor has the same oil inlet and outlet.