The    Vickers Vane Pump    illustrates the difference between a variable vane pump and a dosing vane pump:

First, the two can be distinguished based on the rotational speed. Under the condition of constant speed, the pressure constant output flow can be adjusted by the variable vane pump, the pressure is constant and the flow rate is not adjustable to the quantitative vane pump. The biggest difference is that the shaft of the variable vane pump is installed in a convenient manner.

Second, you can distinguish between the two based on flow and pressure. Simply speaking, after the speed of the fixed vane pump is selected, his flow rate and pressure are determined and cannot be adjusted. The output flow of the variable vane pump can automatically adjust the flow according to the pressure change of the hydraulic system (the size of the external load), that is, the output flow is small when the pressure is high, and the output flow is large when the pressure is low, so that he can save the number of hydraulic components, thereby It simplifies the oil system and reduces oil heating. The disadvantage is that the flow pulsation is severe, the hydraulic system pressure is not stable, the pump life is short, the pump bearing is easy to break, because he is installed with a good heart, and the pump has a loud voice.

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