Forklift Hydraulic Pump - Hydraulic pumps could be either hydrostatic or hydrodynamic. They are usually used in hydraulic drive systems.
Hydrodynamic pumps could be considered fixed displacement pumps. This means the flow throughout the pump per each pump rotation cannot be altered. Hydrodynamic pumps can even be variable displacement pumps. These types have a much more complicated composition which means the displacement is capable of being changed. Conversely, hydrostatic pumps are positive displacement pumps.
Most pumps are functioning within open systems. Usually, the pump draws oil at atmospheric pressure from a reservoir. In order for this process to run well, it is vital that there are no cavitations happening at the suction side of the pump. In order to enable this to work correctly, the connection of the suction side of the pump is bigger in diameter as opposed to the connection of the pressure side. With regards to multi pump assemblies, the suction connection of the pump is usually combined. A general option is to have free flow to the pump, meaning the pressure at the pump inlet is at least 0.8 bars and the body of the pump is often in open connection with the suction portion of the pump.
In the cases of a closed system, it is all right for both sides of the pump to be at high pressure. Usually in these conditions, the reservoir is pressurized with 6-20 bars of boost pressure. In the case of closed loop systems, usually axial piston pumps are utilized. For the reason that both sides are pressurized, the pump body requires a different leakage connection.
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