The function of the direction of the flow control valve is to control the direction of movement of the hydraulic cylinder or hydraulic motor to change the direction of oil flow or break the flow of oil.
Examples of construction of the flow control valve (directional control valve) shown in the image:
Symbols Direction Flow Control Valves
Symbol of the direction of flow control valve on the image 4127
P = channel back pressure R = Channel A, B = Channel cylinder
In the 4128 image (a). control valve neutral position, so there is no flow into the cylinder. At 4128 (b) and (c), actuated control valve. Eg actuated control valve to the left (position raise). It is seen that the control valve will direct the oil to one side of the cylinder while the other side will be directed towards the return ports. Return port here can head to the tank or towards other control valve.
