Hydraulic and Pneumatic | Difference Between pneumatics and hydraulic

In the world of fluid power application, the difference between hydraulic and pneumatic is often covered in a comprehensive manner. These two types of power circuits are actually similar in many ways in that they both use mechanical energy as well as being fluid in execution, terminology, and components. Similarly both systems require a certain type of pump and some valves to control the force and velocity of the actuators.

However, the differences between the two show how and where each may be most useful in relation to your needs.

Hydraulic & Pneumatic

Difference Between pneumatics and hydraulic

The difference between pneumatics and hydraulics actually lies in the medium that is used to transmit the power. Pneumatics use an easily compressible gas such as air or a pure gas. Meanwhile, hydraulics use relatively-incompressible fluid media such as mineral oil, ethylene glycol, water, synthetic types, or high-temperature fire-resistant fluids to make power transmission possible.

Due to this primary difference, some other aspects regarding these two electrical circuits also follow. Industrial applications of pneumatics use pressures of 80–100 pounds per square inch, while hydraulics use 1,000–5,000 psi or over 10,000 psi for specialized applications.

In addition, a tank would be required to store the oil by which it could be drained from the hydraulic system in case of deficit. However in a pneumatic system, air can simply be drawn from the atmosphere and then purified through filters.


In short, their differences are as follows:-

S.no Pneumatic Hydraulic
1. Confined pressured system that use moving air or other gases Confines Pressurized systems that use moving liquids
2. Because gases can be compressed, there is a delay in the movement, the force Liquids are not very compressible, there is no delay in the movement
3. Need for compressor Hydraulic Fluid-Liquid inside system

Cylinder – Container Holding Liquid

Piston – Plunger moving inside cylinder

Pumps – Moves liquid in specific direction(usually against gravity)

Valves – controls the flow of direction (allows flow in one direction)

4. Example:-

Precision drills used by dentists

Pneumatic brakes (Air birack

Tampers used to pack down dirt and gravel

Nail Gun

Dentist Chair


Dump Truck Lift

Hydraulic lift to lift cars

Jaws to lift

Blood in body

used in cars

5. Pneumatic Symbol 

pneuamtic symbol

Hydraulic Symbol

hydraulic symbol

Optimization of strengths

You can count on pneumatic systems for their simplicity of design and low initial cost. This is because air-powered circuits operate at comparatively lower pressures and components can be made from cheaper materials which cuts down on secondary machining costs and operations.

On the other hand, it is not something that you might initially expect from a hydraulic circuit as it requires a power unit which should be a part of your machine. And so, if you are looking to get started in a less expensive way, air circuits may be the right choice for you.

Meanwhile, the cost scenarios are going to be different in the long run. Pneumatic circuits can be 5-10 times more expensive in terms of operating costs.

Apparently, compressing atmospheric air to its normal working pressure requires tons of horsepower. This makes air motor components very expensive to operate. For hydraulics, the higher initial cost can often be offset by the lower operating cost with its higher efficiency. Hydraulic-powered machines operate at higher pressures from 1500–2500 psi and thus generate higher forces from smaller scale actuators.

When there are many hydraulic machines in a certain manufacturing plant, it is ideal to install central power units to benefit from its benefits. Machine noise levels are being reduced substantially, uptime has been increased for all machines, and back up pumps will be available in case a working pump breaks down.

In terms of housekeeping, pneumatic systems are easier to maintain than their hydraulic counterparts. Air-powered circuits are cleaner because its force transmitter is atmospheric air. No problem with any kind of leakage.

However, this can be quite expensive and a typical handheld blow-off nozzle will take about five compressor horsepower to provide air and then maintain 100 PSI.

Thus, even though hydraulics housekeeping can be a problem, proper measures need to be employed to solve the problem. Proper plumbing procedures, preventive maintenance and the right materials can help reduce hydraulic leaks.

Best use for hydraulic and pneumatic

Some Best use of Hydraulics and pneumatics are –


Pneumatics are commonly used in factory set up, manufacturing, mills, building and technology using a central source of compressed air for power. Equally common are medical applications of pneumatics, including a dentist’s high-powered drill. Practically everything can run on pneumatics, including any form of transport. That small tube in the bank’s drive-teller is operated through a high-pressure source of compressed air via pneumatics. there are some example of Pneumatic –


  • Air compressors
  • Vacuum pumps
  • Compressed-air engines and vehicles
  • HVAC control systems
  • Conveyor systems in pharmaceutical and food industries
  • Pressure sensor, switch and pump
  • Precision drills used by dentists
  • Air brakes used by buses, trucks, and trains
  • Tampers used to pack down dirt and gravel
  • Nail guns
  • High pressure bank’s drive-teller tubes
  • Manufacturing and assembly lines
  • Pneumatic motor, tire, and tools


Hydraulics have diverse uses in everyday life and most of them apply to machines. For example, hydraulics are applied to the braking system of a car. When the driver steps on the car’s brakes they only need a small amount of force, but a large force is already generated to stop or slow down a car because it applies equally to all 4 brake pads. works.

Hydraulic applications are also evident in lifting equipment such as wheelchair lifts, digging arms on excavators, hydraulic presses for forming metal parts, and wing flaps on aircraft. The obvious uses of hydraulics are with heavy equipment. there are some example of Hydraulic

  • Elevators
  • Dams
  • Machine tools: hydraulic presses, hoppers, cylinders, and rams
  • Amusement parks
  • Turbines
  • Dump truck lift
  • Wheelchair lift
  • Excavating arms for diggers
  • Hydraulic presses for forging metal parts
  • Wing flaps on aircraft
  • Hydraulic braking system in cars
  • Lift cars using a hydraulic lift
  • Jaws of life

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