Hydraulic Valves

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Valve Structure

  • See cut-away view here - [1]

Power Beyond

POWER BEYOND (Also referred to as high-pressure carryover), obtained by using a sleeved outlet that carries oil under pressure directly from the open center passageway of a control valve to the inlet of a down-stream control valve bank. This sleeve outlet prevents back pressure on the exhaust or return passage of a control valve which normally is not designed to take high pressure. This option also prevents back pressure on spool seals and also does not put back pressure on the built-in relief valve which, if allowed, tends to increase the relief valve opening point to the total of the relief valve’s original setting by the amount of back pressure in the control valve’s exhaust passage. This option is often used to obtain more valve sections or spools than normally obtainable by one control valve bank, or used when additional spools need to be added in the field. Still another use is to obtain a circuit in which it is desirable to have certain valve functions take “Priority” on flow. This is accomplished by having those functions requiring “Priority” flow be controlled by the upstream valve bank equipped with power beyond, then whenever a spool of the power beyond valve is fully activated, this will take all oil from pump and stop the flow of oil to any downstream valve until the power beyond valve spool is returned to neutral, at which time oil will again flow to the downstream valves. NOTE: It is always necessary to provide a tank return port on all power beyond valves in order that the “return” or “dump” oil from a cylinder or motor can be returned to the tank.

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