Metals

Metaldyne Performance Group (called MPG in this article) Plant 1 in Columbus, Indiana (formerly known as Impact Forge) has made significant efficiency improvements to their compressed air system.  With the help of their service provider, IAC Air Compression, MPG has implemented some innovative control on their existing air compressors, added new air compressors with variable capacity control, and tied everything together with a modern central controller.  This installation has been recognized for its wise use of power by their power utility Duke Energy.

Ahresty Wilmington Corporation (AWC) was founded in 1988 and is located in Wilmington, Ohio. Currently AWC employs over 900 people with sales totaling \$192 million. They have grown steadily, all while continuously improving and staying on the leading edge of technology. AWC is a tier-1 automotive supplier servicing their entire customer base in the United States. AWC has established an efficient and integrated production system that incorporates die-casting, finishing, machining, and assembly operation using just-in-time production methods to provide its customers with quality products at a competitive price.

In recent years, we have seen an upward trend of higher production manufacturers wanting to integrate their air gauging quality checks from a stand-alone, outside-of-machine device where the operator is performing a manual check to an automated in-process gauge. There are several reasons for this trend, including higher quality standards, tighter tolerances, as well as running a leaner operation. The benefits are 100 percent inspection of the required geometric callout, as well as handshaking between measuring device and machine to make each piece better than the prior one. It also removes any bad parts.

When a company is considering making an investment of more than a million dollars in system upgrades, it is crucial for them to review all options to get the best return. By exploring energy efficiency impacts throughout the entire compressed air system, vendors can propose projects resulting in both a larger sale for them and increased financial benefits for their customers, while still meeting capital expenditure guidelines. This “best of both worlds” scenario was evident when a foundry in the Midwest was evaluating options for replacing its steam system used to drive the plant’s forging hammers.

Nissan North America operates on a massive scale. The company’s powertrain assembly plant in Decherd, Tennessee, alone encompasses 1.1 million square feet, and manufactures engines for 14 different vehicles. The facility also handles crankshaft forgings, cylinder block castings, and other machining applications. Over the course of one year, the powertrain plant churns out approximately 1.4 million engines, an equal number of crankshaft forgings, and 456,000 cylinder block castings.

EnSave, an energy auditing company based in Richmond, Vermont, recently performed compressed air audits at two facilities of a leading U.S. steel manufacturer. Both plants are mills that melt, cast, and roll steel to produce a variety of products, including: rebar, merchant bar, steel flats, rounds, fence posts, channel bar, steel channels, steel angles, structural angles and structural channels. These products are used in a diverse group of markets, including: construction, energy, transportation and agriculture. Compressed air is provided at 100 psig in both plants for a variety of applications — from optical sensor cooling to pneumatic cylinders for stacking finished products.

A major Midwestern aluminum plant was experiencing dwindling compressed air capacity, primarily due to air leaks. If those capacity issues went unresolved, the facility would have needed rental compressors to keep up with demand. Instead, they turned to flow metering to identify and fix the leaks. In this article, they share their solutions with others who may be having similar difficulties.

Compressed air use in the metal fabrication industry is widespread. It is used to cool, clean, convey and coat a multitude of products and improve processes across the world. In fact, it is difficult to name processes in metal fabrication where compressed air cannot be found. A few processes where compressed air is used include: annealing and pickling, slitting, rolling, welding, stamping, punching, tube making, painting, finishing, turning, drilling, milling and sawing. Many of these processes and applications continue to use inefficient devices to deliver the compressed air, and — worse yet — many companies fail to recognize the simple implementation and significant payoff of improving compressed air efficiency.

Quite a number of worst-case compressed air scenarios have been encountered over the years but none may compare to the conditions that existed in a metal foundry somewhere in North America. For reasons you are about to discover, we will not reveal the name of this factory or its location, in order to protect the innocent from embarrassment.

This metal fabrication and machining facility produces high-quality precision-built products. Over the years, the plant has grown and there have been several expansions to the current location. The company currently spends \$227,043 annually on energy to operate the compressed air system. This figure will increase as electric rates are raised from their current average of 9.8 cents per kWh.