Circular sealing gap
Axial circular sealing gap : Gap created when a piston runs inside a bore (e.g. pump pistons, valve control spools in valves). Providing a centric gap is involved, the leakage will depend on the following [...] circular sealing gap : Gap created between, for example, the end of a cylinder drum for an axial piston pump and the control disc. Here, the leakage is as follows ( K 37 c ): where
Circulation index U
Parameter to determine the minimum oil volume of a container, which relates to the flow rate Q of the pump per minute: The size of U depends on the operating mode and fluctuates between 6 in the case of stationary
Subcircuit
Circuit for a self-contained function, which is, however, also supplied by the main pump. If a subcircuit works at a lower pressure than the main circuit, a pressure-reducing valve is placed at the input
Constant force characteristic
velocity) is dependent on the load. Example: electric motor in series connection, power-controlled pump, compressed air cylinder (connection behaviour of fluid drives). Opposite: position dependent locking
Primary and secondary control
Adjustability of a hydrostatic transmission based on a combination of a pump and motor with adjustable geometric displacement. This ensures the highest rotation speed range is achieved with a good level
Pre-load pressure
outlet line of a system). 2. Pressure to which the oil in a tank is subjected if the suction of the pump requires this. To that end, a rubber diaphragm absorbs the gas at 0.3 to 0.6 bar ( pre-charged oil
Overload protection
ing valve, which starts to open when a configured response pressure is reached and circulates the pump flow rate back into the container. The total power then becomes the power loss .
Speed control circuit
accurately as possible to a setpoint. This action can be undertaken by changing the flow Q 2, i.e. the pump delivery flow (Figure D 41) , or the displacement V 2 of the motor.
Impulse metering lubricator
lubricating oil. The impulse metering lubricator operates on the basis of an air-driven injection pump (interval lubrication).
Single or separate drive for machines
Every machine or even every cylinder , provided its movements overlap with others, has a dedicated pump with a size based on the highest load speed v k required (Figure E 13) . This means that high speeds [...] larger range. In (Figure E 14) the cross-hatched area marks the flow rate gain compared to a constant pump of the same (corner) power.