Pressed for profitability

Without the proper compressor technology, shops face premature failures, high maintenance costs, additional compressor unit purchases and exorbitant downtime

The air we breathe may be free, but the notion that this applies to the compressed air that drives processes and production tools is a myth that no shop can really afford. Although the costs of air compressors may appear minor when compared to pricey production equipment, inefficient or unreliable air systems may be stealing you blind in terms of electrical costs, maintenance, premature failures and, worst of all, unplanned downtime.

There was a time when com-pressed air systems could be more or less taken for granted. Compressor technology was somewhat rudimentary, energy costs were low, processes less sophisticated and just-in-time delivery was a thing of the future. Not anymore. Air compressor design has a great bearing on efficiency and reliability, electric power is expensive and even penalizing, on-time deliveries are often critical, and 24/7 demand on systems is commonplace. Today, an inefficient, inadequate, unreliable or failed compressed air system can waste precious production time as well as put customer relationships at risk.

"In businesses such as body shops, the air compressor is one of the biggest pieces of equipment," says Stuart Silverman, president of Lans Company, an air compressor distributor. "Maybe it's a 20 or 30 horsepower motor, but it is essential and can cause a lot of expense. Shops that are running 60 horsepower compressor motors could save as much as $1,000 per month."

Power savings aside, an efficient compressor can make a huge difference in the operating success of many shops, directly affecting the bottom line. For example, it's no secret that insurers closely monitor shop cycle time. If a paint job gets botched because of faulty air, the resulting rework will throw off the shop schedule, not to mention profits.

Silverman advises that oil or water in a com-pressed air system can present major problems to even smaller shops. With auto paint costing upward to $100 a quart, and special paints such as iridescent types costing even more, a small amount of oil in the air system can cause problems such as "fish eyes" that will cost plenty to redo.

With over 40 years in the compressed air industry, Silverman attributes many air system problems to leaks and negligent maintenance. He has seen many an operation where punctured hoses and improper repairs have not only caused system inefficiencies, but have led to the purchase of additional compressors that were not actually needed.

"A 1/8-inch hole in a hose is going to cost as much air as put out by a ten horsepower compressor," Silverman says. "We had a customer with a 50 horsepower [compressor], and the manager said he needed another one. I knew the operation, and just couldn't believe it was necessary, so, I went to the shop and found that there were leaks everywhere that had been fixed with tape and sometimes not fixed at all. I went in there with a spool of hose, and for about $2,000 I eliminated probably 75 percent of the leaks."

After that, the compressor was running at 60 percent to 70 percent duty cycle. There could have been more unnecessary maintenance costs, or even premature failure of the compressor, Silverman adds.

Silverman considers inadequate maintenance as a core problem for shops. If you run a compressor dirty, run the oil low or don't change the oil often enough, they'll run hot. If you have a leaky system, it will make them run harder, which also makes the compressor run hotter. If your air filter is clogged or belts are out of adjustment, you'll be running slower and hotter. The outcome will be inefficient systems, high maintenance costs, premature failures and, worst of all, unscheduled downtime, he says.

"Any equipment failure we experience usually occurs because of compressed air problems," says Hans Hermann, a purchasing manager that has used air compressors throughout his career. "We have machines that require a high volume of air 24/7, because we do a lot of lights-out manufacturing. So, in order to get that reliability, we're very willing to invest in the right compressor systems."

While the cost of electric power needed to drive its compressors is not a major issue with some users, excessive use of power may be a significant cost that is often swept under the rug. For example, older models of compressors often cause a spike in the electric power load during peak usage periods, resulting in a demand profile that could cost many thousands of dollars per year.

Ed Sullivan is a technology writer based in Hermosa Beach, Calif.