The main technical parameters of Hydraulic Pump
(1) Pump displacement (mL/r) The volume of liquid that can be discharged by the pump per rotation.
(2) The theoretical flow of the pump (L/min) at the rated revolution, the maximum flow rate of the pump can be discharged within the unit time obtained by the calculation method.
(3) the rated flow of the pump (L/min) under normal working conditions; Ensure the pump for a long time to run the maximum output flow.
(4) the rated pressure of the pump (MPa) under normal working conditions, can ensure that the pump can run for a long time.
(5) the maximum pressure of the pump (MPa) allows the pump to exceed the maximum pressure of the rated pressure in a short time.
(6) the rated revolution of the pump (r/min) under the rated pressure, can ensure the maximum number of revolutions for a long time normal operation.
(7) the maximum revolution of the pump (r/min) at the rated pressure, allow the pump to exceed the maximum revolution of the rated speed in a short time.
(8) pump volumetric efficiency (%) pump actual output flow and theoretical flow ratio.
(9) pump total efficiency (%) pump output hydraulic power and input mechanical power ratio.
(10) the driving power of the pump (kW) can drive the mechanical power of the hydraulic pump under normal working conditions.
Performance parameters of hydraulic pump and hydraulic motor
Hydraulic pump and hydraulic motor performance parameters are: pressure, flow, efficiency, power, torque and so on.
(1) pump pressure
Pump pressure includes rated pressure, working pressure and maximum pressure. The rated pressure of hydraulic pump (motor) refers to the maximum working pressure allowed when the pump (motor) runs continuously under standard conditions. It is related to the structural form of the pump (motor) and the volumetric efficiency; Hydraulic pump (motor) working pressure pB(pM) refers to the pump (motor) working from the pump (motor) outlet actual measured pressure, its size depends on the load; The maximum pressure of the pump refers to the limit pressure of the overload operation allowed by the pump in a short time, which is limited by the sealing performance of the pump itself and the strength of the parts and other factors; Working pressure less than or equal to the rated pressure, rated pressure less than the maximum pressure.
(2) pump flow
Pump flow is divided into displacement, theoretical flow, actual flow and instantaneous flow. Pump (motor) displacement VB (VM) refers to the volume of oil output (input) when the shaft of the pump (motor) turns around without considering leakage; The theoretical flow qBt(qMt) of the pump (motor) refers to the volume of oil output (input) per unit time without considering the leakage; The actual flow qB(qM) refers to the pump (motor) working when the actual output (input) flow; Rated flow qBn(qMn) refers to the pump (motor) at rated speed and rated pressure when the output (input) flow. The instantaneous flow qBin of the pump is the flow value of the hydraulic pump at a moment, generally referring to the theoretical (geometric) flow rate of the pump moment. The actual flow rate of the pump (motor) is less than (greater than) or equal to the rated flow rate, allowing for leakage, and the theoretical flow rate of the pump (motor) is greater than (less than) the actual flow rate.
(3) The power and efficiency of hydraulic pump and hydraulic motor
The power and efficiency of hydraulic pump and hydraulic motor mainly refers to input power, output power, mechanical efficiency, volumetric efficiency and total efficiency. For hydraulic pump, the input is the mechanical power PBI, the output is the hydraulic PBT, the ratio of two power is the total efficiency of the pump ηB, the pump output power is less than the input power, the difference between the two is the power loss, including volume loss and mechanical loss, these losses are respectively expressed by the total efficiency ηB, volume efficiency ηBv, mechanical efficiency ηBm. Due to the leakage loss and friction loss, the actual flow qB of the pump is less than the theoretical flow qBt, and the theoretical torsional TBt moment is less than the actual torque TB. The calculation formula related to the pump is:
For hydraulic motor, the input is mechanical power PMI, the output is hydraulic PMT, the ratio of two power is the total efficiency of the pump ηM, the output power of the motor is less than the input power, the difference between the two is power loss, power loss is divided into volume loss and mechanical loss, these losses are respectively expressed by the total efficiency ηM, volume efficiency ηMv, mechanical efficiency ηMm. The actual flow qM of the motor is greater than the theoretical flow qMt, and the theoretical torsional TMt moment is greater than the actual torque TM.
