2. Calculation and selection of basic parameters for hydraulic pumps and hydraulic motors
The hydraulic pump and hydraulic motor are mutually reversible in mathematical models, so the basic parameters are generally the same, including the speed n of the hydraulic pump rotor, the flow rate q of the hydraulic oil, the pump displacement VP, the output power P0, etc. The conversion formula between each parameter is:
When designing a hydraulic system, the following performance indicators should be considered.
2.1 Working pressure refers to the high-pressure inlet pressure Ph of the hydraulic pump (motor) oil, which mainly depends on the working load of the hydraulic pump (motor), and also needs to consider the hydraulic oil inlet and outlet pressure difference Δ P, i.e. Ph Pi. When calculating work pressure, the key is not to exceed the rated pressure of the hydraulic pump (motor), otherwise it may cause overload damage to the equipment. In practical work, in order to meet work reliability, it is usually required that the rated pressure be greater than 25% of the working pressure.
2.2 Working flow rate: The working flow rate q of a hydraulic pump (motor) refers to the volume of hydraulic oil flowing through it per unit time. Due to leakage and other factors, the actual flow rate q is often greater than its theoretical flow rate qη.
If the flow rate is insufficient, it may cause the hydraulic pump (motor) to lose pressure, become empty, and other situations.
