Troubleshooter
Directional control valves – dcv – are use to start, stop and change the direction of fluid flowing through a hydraulic system.
The directional valves designate the type of hydraulic circuit either close or open.
In a hydraulic system these valves are use to establish the direction of motion of a hydraulic cylinder or hydraulic motor.
Type of DCV
Although they may be designed as rotary or poppet style, the spool type directional control is the most common. This design consists of a body with internal passages that are connected or sealed by a sliding spool along the lands of the valve. Directional spool valves are sealed along the clearance between the moving spool, land and the housing. Directional control valves are primarily designate by their number of possible positions, port connections or ways, and how they are actuate or energized.
For example, the number of porting connections designate as ways or possible flow paths. A four-way valve would have four ports: P, T, A, and B. A three-position valve is indicated by three connected boxes.
Actuating or shifting the valve is operated manually, electro-hydraulically, mechanically, hydraulically, pneumatically and electrically.
Flow capacity of directional control valves
The spool type directional control valves in industrial applications are sub-plate or manifold mounted. The porting pattern is industry standard and designed by valve size. Directional control valve sizing is according to flow capacity which is critical to the proper function of the valve. Flow capacity of a valve is determine by the port sizes and the pressure drop across the valve. This mounting pattern and size is designed as a D02 nominal flow 5 gpm, D03 nominal flow 10 gpm, D05 nominal flow 20 gpm, D05H nominal flow 25 gpm,D07 nominal flow 30 gpm, D08 nominal flow 60 gpm, D10 nominal flow 100 gpm.
