Valve 339-4353

Application for valve 339-4353

Quick-coupler systems are used for easy changing of tools on construction machines without the driver having to leave the machine cab. The main functional part of the quickcoupler system is a hydraulic cylinder that opens and closes the quickcoupler lock for the changing process and when closed safely locks the quickcoupler. The valve 339-4353 controls and operates the quickcoupler cylinder.

Product description for the valve 339-4353

The quickcoupler valve is suitable for locking and unlocking a quickcoupler cylinder. When the construction machine is put into operation, the cylinder of the quickcoupler extends automatically and is thus locked. The unlocking is deliberately started by the electrical actuation of a 4/2 way valve. In order to limit the speed for locking and unlocking the cylinder, an orifice is installed in front of the directional control valve.

Because the pump pressure is constantly acting on the bottom side of the cylinder via the directional control valve and the pressure reducing valve, reliable maintenance of the locking pressure is already ensured during normal machine operation. An additional pressure reducing valve, which is set at 120 bar, limits the maximum pressure on the closing side of the quick-change cylinder so that the locking mechanism does not get blocked by excessive pressure.


  • Automatic locking and holding by applied pump pressure
  • Unlocking by switching a 4/2 way valve
  • Adjustable pressure reduction for the locking

Technical specifications

DesgignPort sizesMaximum pressureMaximum flow rate
Spare part Caterpillar 339-43539/16-18 UNF-2B400 bar15 l/min
Further information about our quick coupler valves: Schnellwechslerventile

Hydraulic schematic