On continuously adjustable directional valves:
The flow depends on the magnitude of the pressure drop assumed at the control edges as well as the magnitude of the opening cross-section and with it the swing on the input signal (Figure D 82).
On pressure valves:
Characterises on directly controlled valves the effect of the stiffness of the adjusting spring on the pressure rise with increasing flow rate: the harder the spring, the higher the pressure climbs at Q max. Here pilot-controlledpressure valves are better (Figure D 83).
Figure D 82: Flow rate dependent on Δp and opening cross-section
Figure D 83: Pressure/flow rate diagram of pressure valves