Two compressors? A case study.

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 plant 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.

True, there was a time when compressed air systems could be more or less taken for granted. Compressor technology was somewhat rudimentary, energy costs were low, processes less sophisticated and JIT deliveries was a thing of the future – not to mention lights-out manufacturing.

But for many companies today, most - or all - of that has changed. 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

“Any equipment failure we experience usually occurs because of compressed air problems,” says Hans Hermann, Purchasing Manager at Magor Mold (San Dimas, CA). “We may have been planning on running the equipment lights-out overnight. But when one of the technicians comes in to set up a new job, he has to re-start and finish the job from the night before. So we’d be behind, as much as a day, and that is a big expense.”

That sort of problem seldom occurs at Magor Mold, which has been designing and building precision injection molds for over 30 years. A leader in producing molds for injection molders serving the medical industry, Magor Mold uses the latest in manufacturing technology, including robotics and automated runnerless systems, to maximize production and ROI for its extensive capital investments.

With over 30 years experience in the injection mold making industry, Hermann knows that even advanced, microprocessor controlled equipment if dependent on having reliable compressed air available when and where it’s needed.

The compressors Magor Mold uses are rotary-vane models from Mattei Compressors, Ltd, a favorite of the injection mold industry.

“The rotary vane design is much more efficient than the old piston compressors,” he says. “The piston compressors go up to a pressure, shut off, let the tanks go down, and then the compressor starts again until they go back up. So, if you want to keep your shop pressure at 120 psi, then your piston compressor has to run from 150 to 130 (psi) and you regulate the shop to 120.

What's great about the rotaries is that they'll run constantly at 125 psi, and you don't need to have regulated air in the shop.” Hermann adds that rotary vane compressors such as the Mattei units can run continuous at full pressure or in the automatic mode where it cycles internally. If the compressor controls sense a drop in pressure, as when a machine goes down, it automatically shuts off.

The primary compressor that Magor Mold uses is a 30 HP model that was purchased in 2002. As the company continues to expand and add machinery, Hermann started to see issues with production timing when the Mattei required service.

So he contacted his distributor, Lans Company (Glendora, CA), a major provider of compressed air systems. “We told Lans that we wanted a backup compressor for when ours required maintenance, in order to minimize downtime,” Hermann explains. “They had been providing us with a diesel powered unit for that purpose. But if you are going to schedule maintenance around the availability of your vendor’s backup compressor, that doesn’t always fit your production schedule, and could put you at risk of a failure.”

In order to avoid maintenance scheduling difficulties due to the unavailability, Magor Mold decided to purchase another 30 HP Mattei compressor, certain it would pay for itself. Now if the primary compressor requires service, Hermann switches over to the auxiliary unit and doesn’t miss a beat.

Today, a service call does not affect the production schedule at all.

My thanks to the Lans Company for this information. For information about their capabilities, ( and perhaps an energy chart with a bit better resolution) please click here .