Industrial Utility Efficiency    

Metals

One topic up for discussion in the metal fabrication industry is the assist gas used for laser cutting. The assist gas is fed into the laser head, and surrounds the laser as it cuts the work piece. The assist gas is intended to facilitate a smoother cut, increase cutting speeds and productivity, and to prevent discoloration, oxidation, scale, burred edges and other defects that can arise from the hot cutting temperatures. Since Nitrogen is an inert gas, it is used as an assist gas on many laser cutting systems to prevent oxygen from coming into contact with the metal while it’s being cut. Nitrogen is supplied to users in traditional cylinders, and with on-site nitrogen generation.
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.
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.
As you walk past the “sandblasting cabinet” back in the corner of the plant running alone and without the need for monitoring, does the thought of operational costs enter your mind? When it does, are you happy knowing the cabinet is automatic and does not need a full-time operator? Then, did you say to yourself, I wonder how much that abrasive media costs? How long does it last? Is this a more cost competitive alternative? Is there something that might last longer?
TIGG Corporation, a manufacturer of activated carbon adsorption vessels, custom air receivers and other steel tanks and pressure vessels, substantially reduced its energy costs after implementing equipment, labor consolidation and procedural changes resulting from a compressed air energy audit. The audit was performed at TIGG's 155,000 square feet manufacturing facility in Heber Springs, Arkansas to determine the efficiency of the existing compressed air system and to set a baseline for TIGG's participation in Entergy Arkansas’ Large C&I Custom Incentive Program.
Air gauging relies on a law of physics that states flow and pressure are directly proportionate to clearance and react inversely to each other. As clearance increases, air flow also increases and air pressure decreases portionately. As clearance decreases, air flow also decreases and air pressure increases.
International Wire Group, Inc. (IWG) headquartered in Camden, NY is the largest bare copper wire and copper wire products manufacturer in the United States with expanding operations in Europe. Products include a broad line of copper wire configurations and gauges with a variety of electrical and conductive characteristics , which are utilized by a wide variety of customers primarily in the industrial and energy, electronics, data communications, aerospace and defense, medical electronics and devices, automotive, and consumer and appliance industries.
Compressed Air Best Practices interviewed Doug Barndt (Manager, Demand Side Energy-Sustainability), Joseph Gress (Principal Engineer, Demand Side Energy) from Ball Corporation and Chris Gordon (Compressed Air System Specialist) from Blackhawk Equipment.  
“Sandblasting” is one of the oldest and most used methods of metal treatment. Various abrasive materials may be loaded manually or by a vacuum system pulling the “grit” from a storage tank. A control valve then operates with the compressed air (bypassing the vacuum pump), being forced into the tank pressurizing the receiver. When the high pressure compressed air goes out the discharge line, it pulls the appropriate amount of grit with it to effectively impinge against the targeted metal surface.
This aluminum mill spends $369,000 annually in energy costs to operate their compressed air system. This system assessment recommends actions reducing annual energy costs by $120,000 and improving productivity and quality by delivering clean, dry compressed air.