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Role of Compressed Air in Modern Manufacturing Processes

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Sudhakaran has over 30+ years of experience in the field of thermal engineering and Compressed air treatment.


Where does the role of pure Compressed air play in the modern manufacturing processes?
Technology and technology utilisation are the key drivers of the manufacturing innovation and productivity enhancement, pushing the substantial and rapid transformation the business models and market structures. Apart from the advanced materials and digitalisation in manufacturing, automation and robotics play a key role modern manufacturing processes to make the business model competitive which is the need of the hour in this century to achieve sustainable growth.

While we talk about automation, industry relentlessly rely on pneumatically operated machines because of the better productivity, safety in handling, cost effective and the reliability of the automation processes. Efforts by the Research and Development are on devising innovative manufacturing and production machineries which could function flawlessly and continuously for all the three shifts with minimum manpower for machine operation and supervision.

While the market demands the most competitive products along with reliability, the manufacturing processes looks for cost effective automation which in turn depend on the fourth utility called Compressed air. Compressed air is an important medium for transfer of energy in industrial processes to operate pneumatic cylinders for automation, atomise paint, to power the power tools, air hammers and air bearings.

It is not for no reason that compressed air is known as the fourth utility: the purity of compressed air is so vital that the eventual quality of the product mostly depends on clean and dryness of the air. No processes can afford to have moisture either in the air cylinders or in the painting guns so much so that in the manufacturing parleys moisture is treated as a menace. Compressed air is vital source of energy in the pharmaceutical and food industries where the quality of the end product depends on the purity of the air as Compressed air come in contact with the end product like antibiotics and milk during pasteurisation.

What is Compressed Air Quality Standard ISO 8573.1: 2010?
Compressed air could be generated with inexpensive process but it would turn out to be the most expensive one if impurities like heat, dust, oil and moisture are not completed eliminated. Certain processes in pharmaceuticals need bacteria free air and Ventilators call for virus free air too!

Compressed air Quality Standard ISO 8573.1: 2010, a group of international standards stipulating the purity and quality of Compressed air provide guidelines for the compressed air that could be tolerated in applications in the industrial use. This standard was reviewed and confirmed in 2017 and this version is current and holds good. Even the smallest possible risk of contamination can impair processes such as material handling, process air and product drying, control valves and cylinders and other tools. These adverse effects can often only be resolved at significant expense directly affecting the profitability.

How to achieve absolute Filtration of Dust & Oil?
Development of technology in the generation of Compressed air has been an ongoing activity and so is the innovation in the methods of treating compressed air. New materials and methods were devised in filtering and drying compressed air since 1970s making the process most effective and superior. Compressed air filters using pleated borosilicate glass fibre have been in use ever since with advent of oil injected Screw Air Compressors, as residual oil from these Screw compressors are mostly in the form of mist and aerosols.

In order to remove these miniscule particles of oil, depth filters were used wherein borosilicate glass fibre in matrix form was employed. Oil vapours and odour in the compressed air are absorbed using versatile material called Activated carbon.

Why is Thermal Engineering needed in Refrigeration based Air Dryers?
Specifications of Compressed air dryers and testing methods are specified by ISO 8173:2007. It shows the standard rating parameters of in defining the performance of an air dryer, performance tests that need to be conducted and specifies the test set up for measuring various parameters such as Pressure Dew Point, flow rate, pressure drop, power consumption, system air loss, outlet temperature; noise emission.

We could witness the art of thermal engineering in the design of Refrigeration based Compressed air dryers that one would be astonished to see the compactness of the dryers which occupy least footprint and the enhance efficiency with which it operates. These dryers are the most energy efficient as Compact Aluminium brazed plate heat exchangers are used to transfer the heat and then get the moisture in the air condensed. The cold air from the evaporator is passed inside the precooler minimising usage of external source of energy. These dryers are PLC based and can be controlled remotely using communication protocol making the life of the utility engineers at the factory much easy. The functions of the dryers are remotely monitored from the dryer manufacturers from their service stations.

Major innovation has also seen in the Adsorption dryers utilising the heat of the compression of the Air Compressor. Adsorption dryers make use of desiccants where moisture adsorption and desorption are reversible process. The heat of the compression is utilised for the desorption process making the operation cost drying practically nil. Though the capital investment is higher compared to the Refrigeration based dryers, the cost of ownership over a specified period justifies usage these advance featured dryers.

Why to be prudent & judicious selection of the technology?
As the options and choices are aplenty in the market space, one should be prudent in choosing the products on the cost of ownership over a period time and considering the value of the engineering that it provides. Compressed air as a utility could be of immense value in cost saving provided the selection of the technology is based on the cost of generation of the compressed air and the purity that calls for considering the environment in which the manufacturing unit is located.

In a tropical country like India, where the ambient conditions are much higher compared to the western countries, the specifically designed products suiting the Indian Conditions would make much more sense compared to a product designed for colder ambient conditions. When it comes to Air Conditioners, the models are different for the same heat load, say 1.5 TR for Indian and the Middle East market.

The same is the case with Refrigeration based Air Dryers as the condensing temperature of the Air Dryers have a bearing on the sizing of the Air Dryer and subsequently on the power consumption which is the recurring cost. An Air Dryer designed for the European conditions under perform in the Indian environment conditions if one were to follow the Standard ISO 8573.1:2010.

Our Collaborative approach to spread technology:
Micro, Small and Medium Industries are the drivers of the economy of any country. This fact has been established in different parts of the world it is true in the Indian context as well. MSMEs are adept in developing smart technologies and they co-operate with other manufacturers who use their machines smart. It could be an OEM (Original Equipment Manufacturer) tie-up that results in bulk manufacturing products at which in turn helps the MSMEs make their products competitive in a fiercely competitive market.

Organisations are looking forward to Industry 4.0 to get the competitive edge in their area of operations by integrating Autonomous robots, System Integration, Internet of Things, Simulation, Additive Manufacturing, Cloud computing, Big Data Analysis and above all Cybersecurity.

The 21st Century business calls for innovative and smart manufacturing processes that would employ sensors and predict failures so that remedial measures can employed to make the products reliable yet competitive.