Forward and return stroke
Distance covered by a piston from the starting point to an end point and back to the starting point. Forward stroke : extension of a piston (mostly the same as the working stroke), Return stroke : ret
Damping device
Triggers an actual damping process that stabilises the drive as the load pressure changes. Damping devices can operate mechano-hydraulically as throttle valves or bypass valves or electro-mechanically
Blow-by effect
"Blowing past" a piston seal. With large pressure gradients it can occur that the seal is not pressed against the sealing surface, instead it is pressed into the grove (Figure B 21) .
Influencing the switching time
Depending on the requirements placed on the switching characteristics of a valve (e.g. to prevent switching shocks), the switching speed for the intended actuation element must be slowed down. This ge
Individual pressure compensator
2-way which ensures for load sensing systems based on several different loads connected in parallel that the load sensing pressure difference remains constant at the metering orifice regardless of the
Filter selection
When selecting a filter, the key parameters of filter fineness , dirt holding capacity, and the Pressure difference on the filter should be taken into consideration. During the evaluation, it is not s
Pressure alternation process in positive displacement machines
Is produced on changing from the suction side to the pressure side on hydrostatic displacement machines . Due to the pressure drop or increase that occurs in a very short time. The process is all the
Electro-hydraulic actuation
Hydraulic (pressurised) actuation of a valve by a small, directly solenoid actuated valve (pilot valve). Here the pilot valve is mostly directly on the main valve (Figure E 19) . With this combination
Speed measurement
For speed measurement analogue or digital measuring procedures are used. Analogue tacho generators or rotary encoders are not particularly suitable for low rotation speeds due to their low signal leve
Throttle valve
Flow valve with fixed or adjustable throttling cross-section. Its flow is dependent on the pressure difference at the throttle: the smaller the pressure difference Δp between the (constant) inlet pres