Piston Pumps

The hydraulic piston is designed as a differential piston and moves up and down in the working cylinder of the hydraulic part. During the upward stroke, the ball of the suction valve rises and the liquid to be pumped is sucked into the lower space of the working cylinder. At the same time, the ball of the pressure valve in the piston is pressed onto its seat and the liquid is forced out of the upper annular space of the working cylinder into the pressure line. On the downward stroke, the ball of the suction valve is pressed onto its seat and the ball of the pressure valve rises. The piston displaces half of the medium from the lower chamber of the working cylinder into the upper chamber and the other half into the pressure line.

The piston rod of the air piston motor is connected to the pump piston and transmits its movement in a straight line. Piston movement is generated by alternating pressurization of compressed air across the air motor piston and is controlled by a four-way air valve. As long as compressed air is introduced into the control part via the pressure reducing valve, the thrust piston motor continues to work until the pump has built up sufficient hydraulic pressure in the pressure line to balance the thrust of the incoming compressed air. The pump then remains in the idle position until the hydraulic pressure begins to drop, for example when the pump is used. Now the device continues to pump and also maintains the dynamic balance between air pressure and hydraulic pressure.

The selected nozzle size and the set spray pressure determine the stroke frequency (strokes per minute) and the air consumption, and therefore also the respective spray performance of the pump. All pump parts that come into contact with the pumped medium are made of high-quality stainless steel.