The flowcontrol

Simulation of a simple system with a flowcontrol

In order to control the velocity of a hydraulic motor or cilinder you have to control the flow. In this example the flow to the cilinder is controled by a simple flowcontrol. .

The pressure behind the flowcontrol is determined by the load on the cilinder and is in this case 80 bar. De flowcontrol is adjusted on a flow of 8 l/min. The hydraulic pump delivers 12 l/min so a part of the pumpflow, 4 l/min flows through the pressure relief valve back to the reservoir. The pressure before the flowcontrol is determined by the pressure relief valve, in this case 120 bar. The pressure drop in the flowcontrol (40 bar) and in the pressure relief valve (120 bar) is converted into heat. This kind of flowcontrol is relatively cheap but has a low energy effeciency.