Telescopic cylinderTelescopic cylinder

Check valveCheck valve

Check valve circuitCheck valve circuit

Pilot operated check valvePilot operated check valve

Shuttle valveShuttle valve

Pressure control valvePressure control valve

Relief valve Relief valve Reducing valveReducing valveUnloading valveUnloading valve

Sequence valveSequence valve

Counter balance valveCounter balance valve

Pressure relief valvePressure relief valve

Guided poppet design/Differential Guided poppet design/Differential piston piston

Explode view Pilot operated PR Explode view Pilot operated PR valvevalve

Open / Closed position pilot Open / Closed position pilot operated PRoperated PR

Used of PRUsed of PR

Construction Pilot operated PRConstruction Pilot operated PR

Compound /pilot operated pressure Compound /pilot operated pressure relief valverelief valve

Remote piloting/multiple pre. selectionRemote piloting/multiple pre. selection

Venting Pilot operated PRVenting Pilot operated PR

ValvesValvesDirectly operated pressure reducing valveDirectly operated pressure reducing valve

ValvesValvesDirectly operated pressure reducing valveDirectly operated pressure reducing valve

Direct operated pre. Reducing valveDirect operated pre. Reducing valve

ValvesValvesDirectly operated pressure reducing valveDirectly operated pressure reducing valve

1 - állító elem, 2 - vezérlő vezeték, 3 - nyomórugó,4 - vezérlő tolattyú, 5 - vezető él,6 - rugótányér + résolaj vezeték Y,7 - visszacsapó szelep, 8 - mérőpont

5 – governing edge

6 – spring plate and leakage line

7 – check valve

8 – measuring point

1 – adjusting element

2 – governing line

3 – spring

4 – governing spool

Pressure reduction valve circuitsPressure reduction valve circuits

Pilot operated reduction valvePilot operated reduction valve

Multifunction pressure controlMultifunction pressure control

Uses of multifunction pre. Control valveUses of multifunction pre. Control valve

BiBi--directionaldirectional pressure regulationpressure regulation circuit circuit

(a)

1 12

(b)

23 3

MultiMulti--pressure regulation circuitpressure regulation circuit

(a)

2

3

1

2 3

4

1

(b) (c )

to sy

stem to

syst

em

to sy

stem

BiBi--stage pressure regulation circuit and multistage pressure regulation circuit and multi--stage stage pressure regulation circuit can reduce overflow power loss.pressure regulation circuit can reduce overflow power loss.

SequenceSequence valvesvalves

Sequence valves cause a hydraulic system to operate in a pressure sequence.

They are used to control the order of various actuators of a hydraulic system.

As soon as the inlet pressure reaches a preset pressure value, the sequence valve will open and let oil pass to a secondary circuit.

Sequence valves have two types—direct-acting and pilot-operated.

They can also be classified as internal control and externalcontrol types according to where the control pressure is from.

Sequence valve circuitSequence valve circuit

Sequence valveSequence valve

PressurePressure ControlControl ValvesValves

(a) (b) (c) (d)

One-way sequence valve and counterbalance valve

(a) One-way internal control sequence valve (b) One-way external control sequence valve(c) One-way internal control counterbalance valve(d) One-way external control counterbalance valve

Counter balance circuitCounter balance circuit

Counter balance circuitCounter balance circuit

Unloading valveUnloading valve

SummarySummary

No.No. Pressure Pressure valvevalve

Measure and Measure and control quantity control quantity

Outlet Outlet port to port to

leakageleakage symbolsymbol

11 Pressure Pressure relief relief

Inlet pressure Inlet pressure tanktank to have no to have no drain portdrain port

22 Unloading Unloading valvevalve

Pilot pressurePilot pressure tanktank to have no to have no drain portdrain port

33 Pressure Pressure reducing reducing valvevalve

Outlet pressureOutlet pressure actuatoractuator to have a to have a drain portdrain port

44 Sequence Sequence valvevalve

Inlet/pilot Inlet/pilot pressurepressure

actuatoractuator to have a to have a drain portdrain port

55 CounterbaCounterbalance lance

Inlet/pilot Inlet/pilot pressurepressure

tanktank to have no to have no drain portdrain port

66 Pressure Pressure switchswitch

Inlet port Inlet port pressurepressure

T

p pK

T

K

T

p

P2

1P

L

P2

LLP1 P1

K

P2

P P

K

T T