Industrial Utility Efficiency

# Air Compressors

When selecting an air compressor for your manufacturing operation, the common choice is the industry-standard rotary screw compressor. Known as the work horse of compressed air machinery, the rotary screw compressor comes in a multitude of sizes and power levels. However, centrifugal compressors have seen some exciting technological progress in recent years and offer a wide range of pressures, flow and turndown. Long known for their longevity and durability, they offer higher efficiency, even qualifying for energy rebate programs offered by local utilities and all, notably, produce Class 0 oil free air.

## Substance in Sustainability at Atlas Copco

Having set a goal to reduce their own energy intensity by 20 percent by the year 2020, Atlas Copco has also set the ambitious target for the energy consumption of the products they sell. Using the Global Reporting Index as the way to establish metrics, there is real substance behind the sustainability program at Atlas Copco.

## How to Troubleshoot a Large Motor Drive Safely

Any time you troubleshoot a large motor drive, you run the risk of both electric arc and electrical shock. Arc blasts are less frequent but deadly. They’re most commonly caused by a dropped wrench or other tool that lands across high-energy bus bars in an open cabinet. This kind of short circuit is upstream of protective fuse links and lets loose thousands of amperes of fault current.

## Double-acting Reciprocating Air Compressors for P.E.T. Bottle Blowing

Most P.E.T. bottle-blowing machines require anywhere from 550 psig (38 barg) to 580 psig (40 barg) and an air flow of 247 cfm FAD (420 m3/hr) to 3700 cfm FAD (6290 m3/hr). The air compressor technology used most prevalently for this application is the double-acting, oil-free, water-cooled, reciprocating air compressor. With the higher pressures and air flows that are required, the P.E.T. bottle blowing market is a strong niche market for the double-acting oil-free reciprocating (piston) compressors.

## Sanity Check: Will the Standby Air Compressors Start-Up During Cold Weather?

Several days prior to our visit, during a cold winter evening, the lead air compressor in one mechanical room tripped off (apparently due to a fouled intake filter and low air flow through the machine). A crucial situation then developed: The "stand-by" unit did not start. Maintenance folks had to be called in to get a compressor running. That delay caused low plant air pressure, production curtailment and some defective product. They had yet to determine the conditions that caused the "no-start".

## Matching the Supply and Demand in a Compressed Air System

Production processes get their energy from the air stored at higher pressure in the piping distribution system. The air compressors simply replenish the air that is consumed. It is an important distinction to make. The energy input in compressing the air is supplied to the connecting pipes for delivery to the various demands throughout the facility.

## Oil-free Booster Compressors Aid Pharmaceutical Packaging

In the realm of pharmaceutical production and packaging, the two most important factors with compressed air are reliability and quality. In pharmaceutical plants, our customers have emphasized this reoccurring theme over and over to paint the clear picture that reliable and high-quality air are king.

## Compressed Air Controls

Compressed air system controls match the compressed air supply with system demand and are one of the most important determinants of overall system energy efficiency. This article discusses both individual compressor control and overall system control of plants with multiple compressors. Proper control is essential to efficient system operation and high performance.

## Demand Versus Supply, Parts l and ll

The purpose of this article is to investigate the cause and effect that can occur when you reduce demand with no supply changes and the alternative which will produce positive, long term results which you can take to the bank.

## Compressor Sequencer Problems and Solutions

The goals of this article are to show why sequencers often have problems, and to demonstrate how avoid problems by proper system integration and controls design.