Hydraulics and Pneumatics: A Quick Review of Their Differences

Hydraulic and pneumatic systems are used for many processes. Both pneumatic and hydraulic systems are controlled by valves that direct the fluid to the actuator where the fluid power is converted into mechanical power.

Here are some insights into the differences between pneumatics and hydraulics:

Hydraulics: The Power of Uncompressible Fluids

Liquid is the heart of hydraulics and can be mineral oil, ethylene glycol, synthetic fluid, or water. These liquids cannot be compressed, which enables operators to adapt the flow of fluid to control the system. Hydraulics are often found in heavy-duty machines or equipment, including cars and industrial lift systems.

A typical hydraulic actuator will operate at a pressures of  4,000 psi. It can also hold the force or torque constant without additional fluid.  Fluid incompressibility is the factor here. Also, the loss in power is minimal, as distances between hydraulic pumps and actuator increases.
 

Pneumatics: The Versatility of Compressed Air or Gas

Pneumatics rely on air or pure gas to transmit power. While this gas is compressible, it allows for the same function as hydraulics. Pneumatic systems suit applications in which the overall process is quicker, and where not as much force or precision is required. They’re used in factory automation systems, high-powered drills, and medical equipment.
 
The initial cost of designing a pneumatic system is lower. Some systems rely on only air. Material costs are inexpensive as well. However, long-term costs can be many times more expensive than with hydraulics, while keeping atmospheric air at working pressure requires a lot of power.
 
A big advantage of pneumatics using air over hydraulics for low pressure applications is that the air can be exhausted directly from the actuator meaning that there is only a need for a supply line.
 

Order Hydraulic Motors and Pumps Today

We hope this helped with your understanding of hydraulic systems compared to their pneumatic counterparts. White House Products Ltd., one of the largest hydraulic pump suppliers, offers a variety of products to maintain your hydraulic system. Order online or call us at +44 (0) 1475 742500 today.

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