Introduction To Pneumatic Systems - Overview, Benefits And Limitations

Pneumatic System

A pneumatic system may be termed as just the use of compressed air to do work. However, it goes way beyond that. When compressed air is controlled using series of pipes and valve, complicated systems with mind blowing capabilities can be created. This fact the life force of today's industrial capabilities and automated systems. In this article we shall look at a brief review, advantages and limitations of pneumatic systems.

In the world of technology, there are various methods of introducing work into a system. In most systems that require a tangible among of work the use of pneumatic systems is a viable alternative apart from electrical systems (electric motor) and internal combustion engines.

The word ‘Pneuma’ means air. Pneumatics is all about using compressed air to do the work. Compressed air is the air from the atmosphere which is reduced in volume by a device called a compressor thus increasing its pressure. It is used as a working medium normally at a pressure of 6 kg/sq mm to 8 kg/sq mm for doing work. It can be controlled manually, pneumatically to do work by acting on a piston or vane.

A pneumatic system is a system that uses compressed air to transmit and control energy. Pneumatic systems are used extensively in various industries. Most pneumatic systems rely on a constant supply of compressed air to make them work. This constant air supply is provided by air compressors. The compressor sucks in air from the atmosphere and stores it in a high pressure tank called a receiver. This compressed air is then supplied to the system through a series of pipes and valves.

Advantages of pneumatic systems

Pneumatic systems are widely used in different industries for the driving of automatic machines. Pneumatic systems have a lot of advantages.

• High effectiveness – There is an unlimited supply of air in the atmosphere to produce compressed air. Also there is the possibility of easy storage in large volumes. The use of compressed air is not restricted by distance, as it can easily be transported through pipes. After use, compressed air can be released directly into the atmosphere without the need of processing. 

• High durability and reliability – Pneumatic system components are extremely durable and cannot be damaged easily. Compared to electromotive components, pneumatic components are more durable and reliable. 

• Simple design – The designs of pneumatic system components are relatively simple. They are thus more suitable for use in simple automatic control systems. There is choice of movement such as linear movement or angular rotational movement with simple and continuously variable operational speeds. 

• High adaptability to harsh environment – Compared to the elements of other systems, compressed air is less affected by high temperature, dust, and corrosive environment, etc. Hence they are more suitable for harsh environment. 

• Safety aspects – Pneumatic systems are safer than electromotive systems because they can work in inflammable environment without causing fire or explosion. Apart from that, overloading in pneumatic system only leads to sliding or cessation of operation. Unlike components of electromotive system, pneumatic system components do not burn or get overheated when overloaded. 

• Easy selection of speed and pressure – The speeds of rectilinear and oscillating movement of pneumatic systems are easy to adjust and subject to few limitations. The pressure and the volume of the compressed air can easily be adjusted by a pressure regulator. 

• Environmental friendly – The operation of pneumatic systems do not produce pollutants. Pneumatic systems are environmentally clean and with proper exhaust air treatment can be installed to clean room standards. Therefore, pneumatic systems can work in environments that demand high level of cleanliness. One example is the production lines of integrated circuits. 

• Economical – As the pneumatic system components are not expensive, the costs of pneumatic systems are quite low. Moreover, as pneumatic systems are very durable, the cost of maintenance is significantly lower than that of other systems. 

Limitations of Pneumatic Systems

Although pneumatic systems possess a lot of advantages, they are also subject to several limitations. These limitations are given below. 

• Relatively low accuracy – As pneumatic systems are powered by the force provided by compressed air, their operation is subject to the volume of the compressed air. As the volume of air may change when compressed or heated, the supply of air to the system may not be accurate, causing a decrease in the overall accuracy of the system. 

• Low loading – As the cylinders used in pneumatic systems are not very large, a pneumatic system cannot drive loads that are too heavy. 

• Processing required before use – Compressed air must be processed before use to ensure the absence of water vapour or dust. Otherwise, the moving parts of the pneumatic components may wear out quickly due to friction. 

• Uneven moving speed – As air can easily be compressed, the moving speeds of the pistons are relatively uneven. 

• Noise – Noise is usually produced when the compressed air is released from the pneumatic components. 

In subsequent articles of pneumatic systems, we shall look deeply at the various component of pneumatic systems, their functions and simple designed of pneumatic systems.

picture credit: hydraulicspneumatics

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