In business, visual cues play a key role in creating customer delight and facilitating purchase decisions. While performance & utility of the product is important on one end, aesthetics can in fact make or break your product’s future.  

One such method of “selling an aesthetic experience” to customers is Spray Painting- making it the most prevalent paint application technique due to its versatility and economic viability.  

Compressed air plays a vital role in spray painting and there are multiple methods involved in the spray painting process including Air-atomized applicators, Airless spray, and High-volume, low-pressure (HVLP) spraying.  

Let’s take a look at each of these methods: 

• Air-atomized applicators are highly flexible and can be used on almost any kind of substrate, as the equipment can be adjusted and customized to suit the needs of the operator. Air-atomized applicator consists of a traditional spray gun that combines compressed air with liquid paint to create a pressurized mist that coats the surface.  
• Airless spray propels paint particles at a lower velocity than conventional air-atomized equipment, so there is less loss of paint through overspray. In this method, rather than mixing liquid paint with compressed air, airless application equipment simply forces the liquid coating through a narrow opening to create pressure.  
• In High-volume, Low-pressure (HVLP) technique the paint is released at a lower velocity, yielding less overspray and blowback than conventional air-atomized equipment. The HVLP spray equipment utilizes spray gun atomization technology that propels large quantities of low-pressure air to the gun applicator.  
  

While there are clear visible benefits in Airless and HVLP spraying, they require advanced skill on the part of the operator, making Air-atomized spraying technique the widely preferred one. 

Design of a spray gun 

Paint applied by a spray gun must be even and should not drip, hence the nozzles of spray guns are designed for handling expanding, non-turbulent volume flow with high exit speed.  
Spray guns can also have flat, broad or round spray nozzles to suit different applications.  

Types of spray guns & the compressed air requirement 

Type of spray, consistency and quantity of paint to be applied determines the operating pressure and the nozzle diameter of the spray gun which in turn determines the compressed air requirement. Typically, spray guns require compressed air in the pressure range of 2 to 6 bar with an average air consumption ranging between 10 to 20 cfm.  

Factors to be considered when sizing your compressor: 

A reliable compressor is key to achieving high quality paint finish consistently.  

1. When it comes to sizing air compressors for painting, operating pressure and flow offered by the compressor, are the critical factors to be considered. 
2. The next critical factor to consider is the compressed air quality that the painting application demands. Quality of air is defined based on accepted levels of contaminants such as water, particles and oil. The air produced by any compressor, contains the same substances as the ambient air. This means that apart from dust particles, the RH factor in the ambient air contributes to water vapor and the oil used in the compressor for lubrication purpose also gets carried along with the compressed air. 

It is recommended that the humidity is reduced by drying the compressed air with a refrigerant dryer, and particulate filters are installed, to reduce the amount of dust particles present in the compressed air.  

An activated carbon filter can also be used to ensure there is no oil in the compressed air system. When supplementing other filters with an activated carbon filter, one achieves a quality called “technically oil-free” compressed air. 

ELGi offers a wide range of oil lubricated and oil free Reciprocating and to choose from, along with the downstream equipment to suit vast range of applications. Our extensive network of authorized channel partners across the world can help to choose the best compressor model suiting your painting applications. 

Get in touch with a compressed air expert for your needs here: https://www.elgi.com/in/contact-us/

The use of compressed air spans rudimentary mechanic shops powered by decades-old reciprocating compressors to large scale textile units powered by high volume centrifugal compressors.  While the basic technology has remained fairly simple — powered pistons, screws, or impellers compress a volume of atmospheric air to a required pressure  — the design and use of compressed air systems have evolved to suit the industry needs.

Compressed air and power consumption

For manufacturers, achieving optimal efficiency is always a challenge as compressed air is inherently inefficient. Fossil fuels are more efficient in getting work done for the same amount of energy.  However, compressed air is among the best ways to safely store and use energy.  Thus, compressed air has remained a prevalent energy source for industry.  Manufacturers have innovated to reduce lifecycle cost, improve reliability, and improve air quality.

The Table below shows the typical lifecycle of a compressor.  Nearly 75% of the cost incurred over a ten year period comes from the power consumption.

In talks with Managing Director, Dr. Jairam Varadaraj, The Textile Magazine unearths the determinants of ELGi’s powerful claim in the compressed air business –– “we provide the lowest lifecycle cost in the world.”

In Part One, we followed ELGi’s evolutionary journey in manufacturing and design which makes a compelling case for sales of their air compressors. But ELGi’s approach to after-sales service is what makes them valuable partners for customers in the long-term.

Commenting on ELGi’s relationship with the Indian textile sector, Dr. Jairam Varadaraj said: “As a group we know textiles better than our competitors. This is because we have our own spinning mill in the group. We have been in the business of textiles for 40-odd years now. We know the pain points and challenges. Plus, we are based out of Coimbatore, a premier textile hub. Wherever you go across the country, people in the textile industry know ELGi.”

The company has a strong sales and service network spanning the length and breadth of the country. ELGi has an extensive team of more than 500 sales and service personnel with a maximum response time of eight hours. Elaborating on this, Dr. Varadaraj pointed out: “For us it is not just about responding when a customer calls. It is about restoring air. Today 96-97% of our customers get their air back in less than six hours. That’s a record nobody can beat. In fact, even our competitors acknowledge this strength of ours. We deliver uptime.

Generally we are there in about an hour. That’s the physical infrastructure. We also have a strong system in place where every defect, however small it may be, is registered at the factory by evening. We are also coming out with a SIM card based device which is incorporated in our compressors. It is in the testing phase. While others have also been offering similar services, we are doing it with a difference. The device talks to the compressor and gives a comprehensive performance report through an algorithm. The software then starts predicting. See, any mechanical device will degrade with wear. Failure takes place when you don’t notice this wear. With this monitoring, you will be able to get there before the failure. Predictive maintenance is what we offer. We have supplied about 55 machines with the device. By the end of this year, we will make it standard on all our machines. Many of our competitors offer it usually for large machines and invariably tied up with a service contract. We don’t want to follow that path. We firmly believe that the device is meant for us. More than our customers, we want to know how our machines are performing, for it will help us keep improving and stay ahead of the curve.”