Hydraulic pump, hydraulic motor, Otos, Rexroth plunger pump, Rexroth hydraulic pump
Hydraulic pump and hydraulic motor performance parameters are mainly pressure (commonly used unit for Pa), speed (commonly used unit for R /min), displacement (commonly used unit for m³/ R), flow (commonly used unit for m³/s or L/min), power (commonly used unit for W) and efficiency.
1. Main performance parameters of hydraulic pump
Working pressure: the actual working pressure of the pump, which varies with the size of the load.
1. Pressure (Pp)
Rated pressure: the highest pressure that the pump can operate continuously according to test standards under normal working conditions.
2, speed (NP)
Rated speed: the maximum speed at which the pump can run normally for a long time under rated pressure.
3, displacement and flow
Displacement (Vp): the volume of discharged liquid calculated from the size change of the sealing volume per revolution of the hydraulic pump, that is, the volume of liquid that can be output per revolution of the hydraulic pump without leakage.
Theoretical flow rate (QPT): The volume of liquid discharged by the pump in unit time, without considering leakage, equal to the product of displacement and speed, independent of working pressure.
Actual flow (Q): the actual discharge of the pump during operation, which is equal to the difference between the theoretical flow of the pump and the leakage amount.
Rated flow: under normal working conditions, according to the test standards must ensure the flow, that is, at rated speed and rated pressure pump output actual flow.
4, power
Input power (QP): the input of the hydraulic pump is the torque and speed (angular speed) of the pump shaft, and the input power refers to the mechanical power that drives the pump shaft, that is, the product of torque and speed.
Output power (P): The output of the hydraulic pump is the pressure and flow of the output liquid, and the output power is the output hydraulic power of the pump, that is, the product of the actual output flow and pressure of the pump.
5, efficiency,
Volumetric efficiency (Y): the ratio of the actual pump output flow rate to the theoretical flow rate.
Mechanical efficiency (I) : the ratio of the theoretical torque required to drive the pump shaft to the actual torque of the pump shaft.
Total efficiency () : the ratio of the hydraulic power output of the pump to the power input, equal to the volume efficiency and mechanical efficiency of the product.
2. Main performance parameters of hydraulic motor
1. Pressure (Pm)
Working pressure: the input pressure of hydraulic motor in actual work.
Rated pressure: the highest pressure that the hydraulic motor can operate continuously according to test standards under normal working conditions.
Pressure difference: hydraulic motor input pressure and output pressure difference.
2, speed (nm)
Rated speed: maximum speed that can run normally for a long time under rated pressure.
Minimum steady speed: the hydraulic motor at rated load, no crawling phenomenon of the lowest working speed.
3, displacement and flow
Displacement (Vm) : the volume of liquid fed by the hydraulic motor calculated from the geometrical dimension change of its sealing volume per revolution.
Theoretical flow (QMT): the flow required to reach the specified speed when the hydraulic motor does not leak.
Actual flow rate (QM) : actual flow rate at the inlet of the hydraulic motor. The actual flow is greater than the theoretical flow, and the difference between the actual flow and the theoretical flow is the leakage amount of the hydraulic motor.
4, power
Theoretical power (Pm): The theoretical power of a hydraulic motor is the product of pressure difference and theoretical flow.
Actual power input (Pm): the product of the pressure difference of the hydraulic motor and the actual flow.
Actual output Power (Pmo): the mechanical power output from the output shaft of the hydraulic motor.
5, efficiency,
Volume efficiency (NMV): The ratio of theoretical flow rate to actual flow rate of hydraulic motor.
Mechanical efficiency (NMM): the ratio of the actual output torque of a hydraulic motor to the theoretical torque.
Total efficiency (nm) : The ratio of hydraulic motor output power to input power, equal to the volume efficiency and mechanical efficiency of the product.
