Creating Pressure with Positive Displacement


We get to do with many physics concepts while we are growing up, even though we do not yet understand them. The first time someone sucks on a pipe to siphon liquid out of a container, the fact that the liquid goes upwards by itself before descending under the force of gravity makes no sense at all. Of course, using high-pressure pumps to force a liquid through a system can greatly increase the force of a liquid flowing through a pipe – and it can be put to good use.


At Bestline Manufacturing, we offer a large selection of Cat high-pressure piston pumps, which we also use in our manufacturing. By using pistons to generate force, they work on a similar principle as a car engine. Instead of sucking liquids or gases through a sealed system, the concept of positive displacement traps a fixed amount of fluid or gas and forces that amount through the system and into the discharge area. This process is repeated with every rotation of the piston, where the downstroke cycle pulls in the liquid and the upstroke cycle forces it out.


Although it sounds like a lengthy process, it happens quickly. A complete cycle on a positive-displacement piston is referred to as a revolution. Normally, engines and other components that are powered by pistons have an engine-speed gauge that displays the current revolutions per minute. A vehicle’s internal-combustion petrol engine would typically revolve at between 1000 and 6000 r/min; this speed is controlled by a throttle valve. With a high-pressure pump, the speed is finely controlled as well and it can be linked to a direct-drive gearbox for even more control. This brings us to the implementation of these components.


In a car, the engine creates force, or power, which is transferred to the gearbox. In turn, the gearbox transmits the generated power through the drive shaft of the car to rotate the powered wheel axle and turn the wheels. In sealed, high-pressure systems, the pumps act as the engines that generate the necessary force to displace the fluids or gases in the system. By adding a direct-drive gearbox, the power can be controlled and manipulated for even more control within a larger system. This concludes the basics of positive displacement.


Bestline Manufacturing is your first choice regarding high-pressure pumps and custom-built systems for your business in Johannesburg. We offer a variety of water-jetting equipment that can be manufactured according to your requirements. For more information on how we can elevate your business with quality high-pressure systems, please browse our website for details.