Advantages of pneumatics Cylinders

Both pneumatics Cylinders  and hydraulics are applications of fluid power. Pneumatics uses air, which is compressible, while hydraulics cylinders  uses relatively incompressible liquid media such as oil. Most industrial pneumatic applications use pressures of about 80 to 100 pounds per square inch (psi) (500 to 700 kilopascals). Hydraulics applications commonly use from 1,000 to 5,000 psi (7 to 35 MPa), but specialized applications may exceed 10,000 psi (70 MPa).

 

Advantages of pneumatics cylinders

Clean

Air is used by a machine & is then exhausted to the atmosphere - no return line necessary.

Any leaks will be of air (which is much less of a problem than oil leaks in Hydraulics).

Availability

Air is freely available in the pneumatics

Most factories are pre-plumbed for compressed air distribution - which makes it very easy to set up a manufacturing process

Simplicity of Design And Control

Machines are easily designed using standard cylinders & other components. Control is as easy as its simple ON - OFF type control

Reliability

Pneumatic systems tend to have long operating lives and require very little maintenance.

Because air is compressable, the equipment is less likely to be damaged by shock. The air in pneumatics absorbs excessive force, whereas the fluid of hydraulics directly transfers force.

Storage

Compressed Air can be stored, allowing the use of machines when electrical power is lost.

Safety

Very small fire hazard (compared to Hydraulic Oil)

Machines can be designed to be overload safe.

Advantages of hydraulics

Fluid does not absorb any of the supplied energy.

Capable of moving much higher loads and providing much higher forces due to the incompressibility.

The hydraulic working fluid is basically incompressible, leading to a minimum of spring action. When hydraulic fluid flow is stopped, the slightest motion of the load releases the pressure on the load; there is no need to "bleed off" pressurised air to release the pressure on the load.

From:http://news.china-manufacturer-directory.org/post/Advantages-of-pneumatics-Cylinders.html