What are Piston Pumps, and for what are they used?

Aqueducts provide a means to transfer water from its source, over long distances, to where it is needed. They were first developed by the people of ancient Egypt, Babylon and Assyria and are still used today. However, Rome’s talented engineers perfected these structures and relied on gravity alone to keep the water flowing, even in uphill sections. Today, powerful piston pumps can outperform the force of gravity by orders of magnitude while offering users a diverse range of applications that includes energy production and draining floodwater.

Pumping equipment varies substantially both in terms of its design and its operating principle. The purpose of the earliest machines was to transport water. However, more than two centuries of non-stop industrial growth and two world wars have led to new needs. Modern pumping equipment is frequently the means to transport liquids other than water plus air, steam and various gases, and piston pumps are just one of several types of such equipment now in use.

Cat PumpsUnlike many other models that rely on rotating impeller blades to set their contents in motion, the type under discussion employs a radically different procedure to keep its contents flowing. As their name suggests, and much like an internal combustion engine, these units depend on the reciprocating action of one or more pistons to provide the necessary compression.

During the operating cycle, the direction in which a given piston moves determines what’s happening inside these pumps. As it withdraws, the resulting vacuum sucks in liquid through an inlet valve. When withdrawal is complete, the movement reverses. The inlet valve closes, and the fluid exits under pressure via an outlet valve which then also closes to enable a vacuum to form when starting the next cycle.

The combined vacuum and compression strokes result in a continuous discharge of liquid at a flow rate that can range from as little as 20 to more than 3 000 litres per minute. Most piston pumps are driven by an electric motor or an internal combustion engine and can generate pressures of between 50 and 5 000 psi. In addition to its internal volume and the number of pistons, the motor’s maximum speed, which depends on its horsepower, will also determine the pump’s performance limits.

Most of the industries based in the Johannesburg area rely on the hydraulic pressure produced by a piston pump to drive various forms of heavy machinery. However, at the other extreme, smaller models are widely used to power equipment such as pressure washers and paint sprayers. For the necessary pumps and accessories, many users in Gauteng have learned to rely on Bestline Manufacturing.