A diaphragm pumpis a positive displacement pump that relies on valve technology and reciprocating action to pump fluid through a pipe system. Diaphragm pumps, which may also be called membrane pumps, rely on the concurrent action of check valves, butterfly valves, and flap valves acting on either side of a rubber or thermoplastic diaphragm to exchange the fluid through the system. Diaphragm pumps can achieve this action in one of three ways. The first kind of diaphragm pump acts by sealing one side of the diaphragm in the fluid that is to be pumped, and the other side in air or hydraulic fluid. This allows the diaphragm to flex and move volume throughout the pump chamber. The second type of diaphragm pump acts by employing volumetric positive displacement via an electro-mechanical mechanism that requires a motor drive. In this method, one side of the diaphragm is flexed by the mechanical action, while the other is exposed to air. The final, and most common, type of diaphragm pump employs an unsealed diaphragm with fluid being pumped on both sides. Like the other methods, the flexing of either side of the diaphragm causes the volume to change and thus movement of fluid throughout the system. 

Many farmers choose to use diaphragm pumps due to their versatility and robust performance moving viscous fluids through a system. One benefit of the diaphragm pump is that they do not have internal components (like gears) that rub against each other to cause friction. Because of this, diaphragm pumps do not often need maintenance and thus are a reliable and cost-efficient pump choice. Other notable performance aspects include their ability to achieve high pressures and deliver high accuracy. 

While classic cast-iron or stainless steel models of diaphragm pumps are currently popular among buyers, other materials may also be useful to consider. For example, while stainless steel versions are better able to move acetic acids and lithium chlorides, PVC models are ideal for pumping sodium hydroxide, hydrochloric acid, or sulfuric acids through the system.

Learn more about chemical transfer pumps and diaphragm pumps.