There are hundreds of different types of pumps and pumping equipment, but all have the same basic purpose, which is to move fluid from one point to another. Pumps come in five general categories; direct lift displacement, velocity, buoyancy and gravity pumps. This article will define each of those types and give examples of each type.

The most basic form of pump is the direct lift variety; a well is a simple example of a direct-lift pump. These machines operate by filling a container with the desired liquid, then lifting and dumping the container in order to empty the liquid.

A displacement pump works by filling and emptying an enclosed volume of liquid into a container. There are five different types of pumps in this category: reciprocating, direct-acting steam, rotary, vacuum and air lift. The names refer to the power source used to run the pump.

Velocity (centrifugal) pumps use a rotating part, called an impeller, to pull in the fluid; as the impeller continues to rotate, the fluid is moved through the pump and out the discharge area. Imagine an old-fashioned water-wheel, miniaturised, encased in a circular housing with inlet and outlet holes.

Buoyancy pumps are most often used for marine purposes and use the principle of buoyancy to move the fluid, usually water, through the pump. Gravity pumps are those that can move water from a lower elevation to a higher one using the water itself as power for the pump.

Research is the key to getting the right pumps and pumping equipment for your particular purposes; fortunately, there are several detailed websites on the subject.