hydraulics vs. Pneumatics
- Jan 06, 2018 -
Both hydraulics and pneumatics are useful technologies when it comes to manufacturing heavy machinery and equipment. Each has qualities that make them suitable for different projects.
If you're considering which type of device to use, or you would like to know more about the similarities and differences between hydraulics and pneumatics, then read more about each one and what makes them unique.
In layman's terms, hydraulics use liquid—usually water or oil—to transmit power. Hydraulic technology is used in a variety of machines, like cranes and other construction materials as well as garbage trucks and even car brakes. In a crane, for example, the engine pushes hydraulic fluid through thin pipes in order to have better control over the arm.
A big advantage of hydraulics is that liquid cannot be compressed. Think about doing a belly flop into the pool and how much it hurts. That's because water won't squeeze downwards when you slam against it. This property of liquids makes them ideal for creating strong machinery.
Because liquid cannot be compressed, hydraulic systems can handle much more pressure than a pneumatic system can. There's also no delay in the movement of a hydraulic machine. Water hydraulics, specifically, are also cost-effective because water is inexpensive and easy to transport.
Because hydraulics use liquid as an energy source, there is a risk of valves, seals and hoses leaking. Hydraulic fluid can also corrode parts of your machinery. Hydraulic machinery also cannot be used in food manufacturing or anything else that could possibly be contaminated by hydraulic fluid leaks.
It also takes a lot of energy to make a thick substance like oil move quickly. Hydraulics that use oil also cannot dump the liquid; they have to reroute them back to a reservoir.
Instead of liquids, pneumatic systems use gas to transmit power. Just like hydraulics, pneumatics are used mainly in mining and general construction, but the technology is also used in dental equipment, like dental chairs, drills and other tools. Jackhammers, air compressors, vacuum pumps and air brakes on buses and trains are also common pneumatic devices.
There are many advantages to using a pneumatic system over a hydraulic one. Because pneumatics use gas, there is no moisture that can corrode internal parts of the system. You also won't have to worry about liquid leaking out of the valves.
Air-based also means that pneumatic systems have simpler designs made from less expensive material. Pneumatic systems are also environmentally friendly because the compressed air can be dumped straight into the atmosphere without causing harm. They also last a long time and require little maintenance for upkeep, making them an ideal piece of equipment for many.
While there are quite a few advantages to pneumatic devices, there are also some disadvantages. The biggest disadvantage of pneumatic technology is that it can't reach as high of a pressure as hydraulics can. Also, gasses are easily compressed—unlike liquids—so there's a delay in the movement of pneumatic devices.
While it might be less expensive to manufacture and install a pneumatic device, they are generally more expensive to run because of the energy needed for heat production while compressing air. For low-scale construction or mechanical jobs, pneumatic systems are a great alternative to hydraulics; however, it is better to choose something stronger for a larger project.
So, as you can see, hydraulics and pneumatics are both common technologies used for different reasons. Hydraulic machinery is best suited for large-scale construction or manufacturing projects, while pneumatic devices can be an economical choice for smaller jobs.
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