Pneumatics and Hydraulics

Pneumatics and Hydraulics

Pneumatics

  • Pneumatics is the technology that makes use of gas (usually compressed air) to create motion or some form of mechanical work.

  • Compressibility of the gas in pneumatics is its primary feature. It means you can push the gas into a smaller volume, increasing its pressure.

  • A common use of pneumatic systems is in tools and machinery. For example, pneumatic drills and other power tools are powered by pressurised air.

  • As gases can move quite freely, pneumatic systems are not as precise as hydraulic systems. However, they are typically lighter and cheaper, making them suited to a wide range of applications.

Hydraulics

  • Hydraulics utilise incompressible fluids to transmit force and do work. The liquid used is typically an oil of suitable viscosity.

  • Hydraulic systems often apply to heavier duty tasks like lifting heavy weights. Hydraulic car jacks and excavator arms are great examples.

  • Incompressibility is the main feature of the hydraulic system. It allows the system to lift or move heavy loads with relatively little input force.

  • Because liquids don’t compress or ‘spring’ like gases do, hydraulic systems can be very precise and powerful, albeit heavier and more expensive than their pneumatic counterparts.

Pneumatic and Hydraulic Systems

  • Both systems operate under the principles of Pascal’s Law stating that pressure exerted on a fluid is transmitted undiminished in all directions.

  • The major difference between the two systems involves the medium used (gas for pneumatics, liquids for hydraulics) and the resulting characteristics; pneumatic systems are lighter and less expensive, while hydraulic systems are more robust and precise.

  • Safety is a key aspect in the design and implementation of these systems. Both systems must be designed to withstand the pressures they will be subject to, and fail-safes must be included to prevent dangerous malfunctions.

  • Remember to investigate and compare contrasting applications of both pneumatic and hydraulic systems so you can understand their functionalities and the reasons behind their uses in various contexts.