Industrial Utility Efficiency    

Metals

A steel distribution and processing company has upgraded and consolidated the compressed air systems in two of their distribution and processing facilities for big energy savings. The previous compressed air systems were running in modes of operation with very low efficiency. A complete replacement of the two systems with new air compressors and dryers has reduced the energy consumption significantly.
A zinc producer spends an estimated $516,000 annually on electricity to operate the air compressors in a compressed air system at its north American plant.  The current average electric rate, at this plant, is 5 cents per kWh, and the compressed air system operates 8,760 hours per year. This system assessment recommended a group of projects able to reduce these energy costs by fifty-one percent (51%) to an annualized $270,000.  The simple payback of the project was 15 months – without taking into account potential incentive dollars from the local utility.
The facility uses a large amount of electricity to manufacture laminated glass in the autoclave process. This process is the largest consumer of compressed air in the facility which made compressed air a major target in reducing energy costs for the facility. As the volume of compressed air in the autoclave is significant, the system is constantly pressurized with large 150 HP air compressors to reduce production times and fill times of the autoclave.
The company specializes in fabrication of precision assembled customized parts for OEM’s and system integrators. Since 1997 the company has steadily grown in size and capacity as the demand for its high quality fabrications has increased.  Through the years, many new CNC machines, laser cutters and powder coat painting operations have been added, but with all the expansion the facility has amazingly kept the plant compressed air consumption low. This has been achieved by following excellent “best practice” compressed air efficiency principles and by keeping watch on system waste.
Paying close attention to compressed air use is paramount for identifying potential energy-saving projects. The engineering team at Ball Corporation has been well aware of this fact for years. An active member in the Environmental Protection Agency’s ENERGY STAR® program, Ball Corporation scrutinizes manufacturing processes to maximize the energy efficiency of compressed air systems in each of its plants.
FABTECH 2016, North America’s largest collaboration of technology, equipment and knowledge in the metal forming, fabricating, welding and finishing industries, welcomed 1,500 exhibiting companies and a total of 31,110 attendees from over 120 countries last week to the Las Vegas Convention Center.
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.
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.