Proportional spool valve (slip-on coil) WDPFA04

Proportional spool valves NG4-Mini

Direct operated proportional spool valve with 4 connections in 5-chamber system. Precise spool fit, low leakage, long service life time. The volume flow adjustment takes place by a Wandfluh proportional solenoid. Proportional to the solenoid current, the spool stroke, the spool opening and the valve volume flow increase. For the control, Wandfluh proportional amplifiers are available (see register 1.13).

Proportional valves Proportional spool valve (slip-on coil) WDPFA04

Proportional spool valve
Flange construction

  • Qmax = 20 l/min
  • 3 volume flow levels
  • QN max = 12 l/min
  • pmax = 350 bar


Proportional spool valves are perfectly suitable for demanding tasks due to the high resolution, large volume flow and low hysteresis. The applications are in the industry as well as in the mobile hydraulics for the smooth control of hydraulic actuators. Some examples: rotor blades control of wind generators, forestry and earth moving machines, machine tools and paper production machines with simple position control, robotics and fan control. Miniature values are used where both, reduced dimensions and weight are important.​