Instrument air is just one of a myriad of applications of compressed air in the manufacturing sector. It finds many other uses in process such as aeration, powder transfer, motive power for machines and so on. In the majority of manufacturing applications, the ‘standard’ model air compressor, along with its regular options, will meet the application’s needs. But in a significant number of situations this isn’t the case, explains William Chan, engineered products manager with air compressor technology group, Champion Compressors.

“We’re seeing regular requests from the manufacturing sector for ‘tailored’ or non-standard air compressors - often for instrument and process control air applications,” Chan explains. The reasons for opting for a tailored air compressor solution are many, but most come down to issues pertaining to the air compressor’s location and environment, the required air quality, the air compressor’s duty cycle and multi-compressor sequencing.

Airend at heart
“The ‘engineered’ air compressors are designed and built from the ground up at our Melbourne headquarters,” Chan says. “Instrument and process air units tend to range in size from 37 to 250 kW, with output flow capacities anywhere between 200 to 1000 CFM at 8 to 10 Bar. The element common to all our engineered solutions, no matter how tailored, is the well-regarded Sullair airend.”

Extremes and duty cycles
More extreme process environment conditions impact on the final engineered design. “Protection of the air compressor and ensuring safe shutdown in certain manufacturing environments can be crucial,” says Chan. “For example, in certain chemical industries the environment can be quite caustic or acidic, so we’ll opt for stainless steel compressor construction and components. In others, we’ll apply anti-corrosive paints and surface treatments.”

Where an air compressor is to be located in explosive atmospheres, often found in the oil and gas or chemical industries, new parameters come into play--most particularly fire detection and protection. Here, onboard fire detection systems are fitted to the compressor, along with either foam or powder-based extinguishing systems.

Multi-stage air compressor systems also fall into the area of ‘engineered solutions’, and often prove necessary in manufacturing applications. These provide the level of redundancy and security required in essential compressed air applications. “Where the compressed air system comprises three or more machines, there is great benefit in sequencing on a rotational basis--specifically in long-term maintenance and performance,” Chan says. “We design multi air compressor systems with sequenced or staged control system, using either the customer’s existing on-site data communications networks, or onboard skid mounted compressor-to-compressor communications.”