How hydraulic systems work

Hydraulic systems are used in a great many aspects of our daily lives. They are used in much of the machinery and transport that we use every day. They can be simple or complex depending upon the use but they all basically work in the same way. So, how do they work? Take a look at these articles.

What’s the connection between a water pistol and this gigantic crane? On the face of it, no connection at all. But think about the science behind them and you’ll reach a surprising conclusion: water pistols and cranes use the power of moving liquids in a very similar way. This technology is called hydraulics and it’s used to power everything from car brakes and garbage trucks to motorboat steering and garage jacks. Let’s take a closer look at how it works!

Photo: This crane raises its giant boom into the air using hydraulic rams. Can you spot the rams here? The main ones are shining silver in the sunlight in the center of the picture. There are also rams supporting the stabilizers: feet that extend out near the four wheels to support the crane at the base when the boom is extended (they’re shaded with orange and gray stripes).

You can’t squash a liquid!

Gases are easy to squash: everyone knows how easy it is to squeeze a balloon. Solids are just the opposite. If you’ve ever tried squeezing a block of metal or a lump of wood, with nothing but your fingers, you’ll know it’s pretty much impossible. But what about liquids? Where do they fit in? You probably know that liquids are an in-between state, a bit like solids in some ways and a bit like gases in others. Now, since liquids easily flow from place to place, you might think they’d behave like gases when you tired to squeeze them. In fact, liquids are virtually incompressible—much like solids. This is the reason a belly flop hurts if you mess up your dive into a swimming pool. When your body smacks into the pool, it’s because the water can’t squeeze downwards (like a mattress or a trampoline would) or move out of the way quickly enough. That’s also why jumping off bridges into rivers can be very dangerous. Unless you dive correctly, jumping off a bridge into water is almost like jumping onto concrete. (Find out more about solids, liquids, and gases.) Click here to continue

Further information

How do hydraulics work?

How hydraulic machines work

Basic hydraulic system theory