Difference Between Hydraulic System and Pneumatic System

Difference Between Hydraulic Systems and Pneumatic Systems

Difference Between Hydraulic Systems and Pneumatic Systems with Tabular Form

The Key Difference Between Hydraulic systems and Pneumatic systems is that In Hydraulic system liquid/oil is used to transmit power, whereas in Pneumatic System compressed gas is used to transmit power.

Comparison Between Hydraulic Systems and Pneumatic Systems with Tabular Form

Comparison Chart

Hydraulic systems Pneumatic systems
The working fluid is hydraulic oil. Working fluid is compressed air.
As oil is incompressible, oil can be pressurized to very high pressure. (500 bar or even more) Air is compressible; hence air can be pressurized to lesser pressure. (Only up to 10 bar approx.)
Since pressure is high, the force developed is also very high (thousands of tones). Since pressure is very less, the force developed is very less (up to I ton)
Since pressure is high, components are very strong, made of steel, and are heavy. Components of the pneumatic system are lighter in weight, are made of aluminum.
As oil has more viscosity, it cannot flow fast. Hence hydraulic systems are slower in operation. Air has very less viscosity, it can flow fast. Hence pneumatic systems are quicker in operation.
Due to continuous recirculation, the temperature of oil increases. The harder it runs, the cooler it works. Free expansion of air in cylinders and motors causes a chilling effect.
Hydraulic oils are petroleum-based oils; they are inflammable and there is every chance of fire hazard if neglected. No chance of fire hazard. Hence pneumatic tools are preferably used inside mines, where flammable gasses may present.
Leakage of oil results in dirty and slippery Surroundings that may lead to accidents. The very clean and dry surrounding is maintained.
The pump used is a positive displacement pump, So a pressure relief valve is necessary No need for a pressure relief valve.
There is no need for a separable lubrication System, because, hydraulic oil itself is a lubricant. A lubricator is necessary. Oil is mixed with the compressed air in the lubricator and then supplied to the system.
Applications: CNC. Machine tools, earth-moving machines, automobiles. aviation etc Applications: Material handling systems, hand tools mining works, automation, automobiles, etc.

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