What is a sprayer pump?

Sprayer pumps are special pumps intended to work with an agricultural spraying system to deliver fluid from a tank and through the spray nozzle tip onto the crop. Sprayer pumps work with other system components including the spray nozzle or gun, nozzle tips, the fluid tank, pressure regulators, valves, gaskets, and other accessories in order to be customized for the ideal performance of specialized applications.

What type of sprayer pump do I need?

Common sprayer pump types include a diaphragm, centrifugal, piston, and roller pumps. Roller, diaphragm, and piston pumps all fall under the category of positive displacement pumps. These pumps are self-priming and are typically selected to operate at high pressures.

Diaphragm pumps are the go-to positive displacement pump selected for the application of abrasive or corrosive pesticides. This is because diaphragm pumps can tolerate high-pressure applications of a variety of tough chemicals.

Piston pumps are likewise a popular choice and are suited best for low-flow and high-pressure applications such as handheld spray guns. Positive displacement pumps produce a flow that is directly proportional to the speed of which the pump operates. Thus, they require relief valves and bypass lines between the pump outlet and the nozzle shut-off valve in order to ensure efficiency and uniformity.

For low-to-medium-pressure applications, the user may choose to select a non-positive displacement pump. These pumps are durable and operate using a rotating impeller that feeds liquid systemically rather than pumping per stroke. These pumps must be primed, but do not require relief valves or bypass lines.  

How to select a sprayer pump

You should select your sprayer pump based on your intended application of chemical or herbicide and the projected area that you intend to spray. When selecting the correct sprayer pump for your operation, always size the pump while taking into consideration your intended application rate, average ground speed, agitation requirements, and application area. Designs may differ from pump-to-pump in construction materials, inlet/outlet sizes, and performance specifications, but most pumps contain the same key features to satisfy pump pressure and flow requirements.

Spray pump pressure and flow requirements can be determined using a simple mathematical equation to calculate agitation requirements. For liquid products, consider tank volume in either liters or US gallons multiplied by 0.05. For wettable powders and flowables, consider that same tank volume measurement multiplied by 0.125