How Does Hydraulic Machinery Work?

Have you ever wondered how an excavator effortlessly lifts a huge bucket of topsoil, or how hydraulic floodgates close and can withstand so much pressure? In this short article, we outline the principles of hydraulics.

Liquid fluid power

The essence of hydraulics is liquid fluid power, when a liquid is pressurised, forcing it down a cylinder, which is the main principle of hydraulic power. The fluid (water or oil) is controlled by pressure controls that open and close, directing the flow of the fluid through hoses, cylinders and pipes.

Pascal’s Law

In 1653, a French Mathematician by the name of Blaise Pascal discovered a fluid principle; Pressure change of any amount, in any direction, an incompressible fluid will exert equal pressure in all directions. Simply put, if you force fluid down a pipe or hose, it will exert the same pressure at the other end, as was exerted at the outset.

What makes hydraulics so popular?

The reason hydraulics is so popular lies in the huge amount of power that can be transferred through hoses, cylinders and pipes. Many industries rely on hydraulics, which rose to prominence during the Industrial Revolution. The fluid is typically an oil, while the cylinders and motors create the power that is fed through the system, opening and closing valves as required. If you need hydraulic repair in Sydney, there is a specialist firm on your doorstep and they have all the solutions, with repair maintenance and system design.

Hydraulic oil

Today’s hydraulic oil is petroleum based with some special additives; aside from providing the power, hydraulic fluid needs to lubricate components. Companies that need a custom hydraulics system can consult with a leading hydraulics specialist, experts that engineer the components to a very high standard, with a design to fit your factory.


Filters remove small particles that somehow find a way into the fluid and they are located at easy-to-reach places, so replacement can happen. There would be a team of maintenance engineers to look after a major hydraulic system; leaks are common, as the system works at very high pressure. The role of hydraulic system repair is to keep the system online and specific tasks must be carried out according to a strict schedule.


Of course, high-pressure fluid running through a network of hoses, pipes and cylinders, does require effective seals, which are high-performance and do need to be replaced periodically.

Hydraulics have been around since the Roman times and since the 17th century, we began to understand fluidity and how we can transfer power.

Post Author: Hattie Braden