Directional control valves are divided into solenoid control valve and hydraulic control spool valve. The solenoid control valve is operated by solenoid(s) while receiving an electric signal, while hydraulic control spool valve is operated by hydraulic power pushing the sliding spool to move forward and back forward. Finotek's directional control valves guarantee high performance in the high pressure hydraulic system through smooth spool direction change.
Directional control valves can be found in hydraulic system of industrial machinery and the most essential elements in hydraulic equipment too. They permit the flow of liquids into distinct routes from 1 or more additional sources. They generally contain a spool inside a cylinder that is electrically or mechanically controlled. The motion of switching the spool allows or restricts the hydraulic flow, so the hydraulic executive devices such as cylinder is controlled by fluid flow then.
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http://www.finotek.com/products/directional-control-valves
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