Working principle Verderair double diaphragm pump

The Verderair diaphragm pump is an air-operated, positive displacement, self priming pump. The drawings show the flow pattern through the pump upon its initial stroke. It is assumed the pump has not been primed prior to its initial stroke.

A. The air valve directs pressurized air to the back side of diaphragm 1. The diaphragm acts as a separation membrane between the compressed air and the liquid. The compressed air moves the diaphragm away from the center block of the pump. The opposite diaphragm is pulled in by the shaft connected to the pressurized diaphragm. Diaphragm 2 is now on its air exhaust stroke; air behind the diaphragm has been forced out to the atmosphere through the exhaust port of the pump. The movement of Diaphragm 2 toward the center block of the pump creates a vacuum within chamber 2. Atmospheric pressure forces fluid into the inlet manifold forcing the inlet ball valves off its seat. Liquid is free to move past the inlet ball valves and fill the liquid chamber.

B. When the pressurized diaphragm, diaphragm 1 reaches the limit of its discharge stroke, the air valve redirects pressurized air to the back side of diaphragm 2. The pressurized air forces diaphragm 2 away from the center block while pulling diaphragm 1 to the centre block. Diaphragm 2 forces the inlet ball valves onto its seat due to the hydraulic forces developed. These same hydraulic forces lift the discharge ball valves off its seat, while the opposite discharge ball valves is forced onto its seat, forcing fluid to flow through the pump discharge. The movement of diaphragm 1 to the center block of the pump creates a vacuum within the liquid chamber 1. Atmospheric pressure forces fluid into the inlet manifold of the pump. The inlet ball valves is forced off its seat allowing the fluid being transferred to fill the liquid chamber.

C. Upon completion of the stroke, the air valve again redirects air to the back side of diaphragm 1, and starts diaphragm 2 on its air exhaust stroke.

Diaphragms are pressure-balanced to ensure longer life. High-pressure, high efficiency operation is achieved by the pump’s unique design. Suction and discharge valves can be either ball valve or cylindrical valve.

Please contact us through the contact form or call your local supplier.