The four Space-Ray infrared tube heaters mounted on the ceiling of Austin Jet's maintenance hangar in Horseshoe Bay, Texas, keep workers and equipment warm during cold weather.

The company installed four gas-fired infrared tube heaters made by Space-Ray of Charlotte, N.C., in a maintenance hangar at Horseshoe Bay Resort Airport in Horseshoe Bay, Texas, where the winters can get cold indeed.

The 12,500-square-foot, uninsulated metal hangar houses the helicopters and fixed-wing aircraft maintained by 15 Austin Jet employees. Each year, a few cold spells bring central Texas temperatures down into the teens and 20s, chilling the workers and making it difficult for them to work.

That is why, early in 1999, Austin Jet purchased four Space-Ray ETU200 infrared tube heaters from Bolinger Sales Co. of Fort Worth. Austin Jet mounted the heaters side by side on the 28-foot-high ceiling above the main work area in the hangar. Each of the Space-Ray units generates up to 200,000 Btu per hour, heating the workers, aircraft, and equipment, a more energy-efficient process than conventional forced air heating systems, which heat the air in a structure from the top down.

During cold periods, operators manually adjust the Space Ray heaters to raise the temperature of the hangar working area to 68°F. According to Bill Lucy, senior vice president and partner of Austin Jet, the Space-Ray heaters warm up the hangar work space within 20 minutes. Lucy credited the heaters with improving the working environment for the maintenance staff and increasing the safety of Austin Jet's maintenance operation, since it is more difficult to work on a cold, soaked aircraft. "The heaters also have eliminated delays due to cold weather when using temperature-sensitive products, such as paint and adhesives," said Lucy.

Dip rooms require controlled temperature and humidity. Arrow contacted Grinnell Mechanical Contractors to help design a production room. According to Michael Grinnell, the company's president, the new enlarged dip room had to meet Class 10,000 cleanroom guidelines with temperature and humidity controls. To do this, the relative humidity needed to drop from 28 percent to 15 percent.

To control the atmospheric requirements, Grinnell brought in Munters Cargocaire of Amesbury, Mass., to design a system that would maintain the room at 68°F with 15 percent relative humidity. Munters suggested a specially designed Cargocaire HCD-series desiccant dehumidifier. Desiccant dehumidifiers work by directing the room's airflow to the face of a slowly rotating wheel that holds a desiccant, a solid, adsorbent material that attracts and holds water on its surface. Desiccants can hold from 10 to 1,000 percent of their dry weight in water vapor.

The process airflow is pulled through corrugated honeycomb openings on the face of the wheel impregnated with desiccant, which captures moisture. Dehumidified air is released into the working environment. During the process, the desiccant slowly becomes saturated. A second flow, of reactivation air, is a heated stream concentrated on a small part of the wheel. As this airstream passes, it heats the desiccant to remove the moisture and expel it.

A series of dump trucks feeds up to 1,000 metric tons an hour of construction materials that the F893 pours, spreads, and levels to widen roads.

During its operation, the F893 pushes along a series of dump trucks carrying road building material they feed into the front hopper of the road-widening machine. A transversal belt conveyor located beneath the receiving hopper extracts material from the machine's side so that an adjustable offset blade mounted on the rear of the F893 can spread and level the material to the desired height and width.

Operators can work on either side of the road by reversing the belt's direction and fitting the offset blade on the right or left side of the road widener. The blade's length is also adjustable by means of bolted extensions from 8.2 feet for transport, to its full working width of 10.5 feet. The machine's operator station also can be placed in offset position on the left or right when that side of the road is being widened.

Hydraulic controls enable the F893 operators to adjust the blade's leveling height to 11.8 inches above or below the road level, and its slope to plus or minus 15 degrees.

Franex designed an optional hydraulic crane that can be used to remove the conveyor or blade extensions. This crane is fitted with a rear transversal brush and a side brush that reach up to 9.8 feet in width, enabling the F893 to function as a sweeper.

A digital imaging system can check 3,000 turkey carcasses an hour to ensure that they meet slaughterhouse quality demands.

To speed things up, Rennes-based Cemagref, a French public research institute devoted to agricultural and environmental engineering, joined Edixia, an industrial vision specialist in Vern Sur Seiche, and the Interprofessional Committee for French Turkeys in Mordelles to develop a digital imaging system that can characterize the quality of as many as 3,000 turkeys an hour.

The imaging system is designed to detect defects in plucked turkey carcasses. These defects include tears in the skin, hematomas, and nicks or gaps in the turkey's flesh. The French researchers used a Minolta CM 508i spectrocolorimeter to count and characterize each type of defect. They designed a specific color image acquisition unit based on the Sony 3 CCD color camera that rapidly inspects passing turkey carcasses suspended from an automated abattoir line.

Algorithms developed to segment color images detect and identify defects, so they can be displayed for operators by a single characteristic color, such as red on a black background, while the computer swiftly accepts or rejects the carcass.

The digital imaging system has undergone tests at the turkey slaughterhouse that is operated by LDC of Sable sur Sarthe, and will be installed next on an industrial production line for field demonstration before being commercialized.

Key to the tensile test was a method of gripping the nanotubes. Physics professor Rodney Ruoff said the researchers used a "nano-welding" technique whereby they focused an electron beam on the nanotube at the point where it loosely attaches to the cantilever of the micromeasurement device by weak van der Waals forces. Residual hydrocarbon gases in the electron microscope decompose, he said, building a carbonaceous deposit that adheres nanotube to cantilever. The attachment is not perfect; it fails before the nanotube breaks about half the time. Still, it succeeds enough to yield valid data, Ruoff said.

Because the nanotubes are multiwalled, researchers were careful to attach the cantilevers only to the outermost shell. A relatively weak interaction between nesting nanotubes lets the outer shell carry the load, Ruoff said. For the first time, researchers measured "the tensile strength of a single nanotube, namely the outermost shell. And the highest strength value, 63 GPa, exceeds that of any reported value for any type of material," Ruoff said.

Taking the lower density of carbon nanotubes into account, Ruoff pronounced the outer shell of the nanotubes about 80 times stronger than high-grade steel.

"Since time is critical, SWAT gets samples to customers within 10 days, and sooner when we have accelerated bid deadlines," said Chromalox design engineer Amy Barker. "To ship on time, we have to receive consistent, high-quality supplies within five to six days." This is typically the case with wire use, she added. Nonstandard wire typically takes from six to 12 weeks from most vendors, she said. Furthermore, many wire suppliers have minimum orders of 40,000 feet, and balked at SWAT's low-volume demands of several hundred feet of wire, she added.

When a manufacturer of color printers for desktop applications searched for a supplier of print head heaters, Chromalox needed to design, manufacture, and ship 10 prototype heaters within five days, but did not have the necessary full-hard wire on hand. Chromalox contacted California Fine Wire of Grover Beach, Calif., a manufacturer of specialty wire products. "CFW stepped in to get us the full-hard wire we needed within our deadline time," said Barker. When Chromalox had to change the wire gauge, CFW sent the new wire via overnight delivery, helping the company meet the OEM's design, delivery, and cost goals, she added.

Carpenter Technology found its Project 7000 15Cr-5Ni stainless steel 3.5 to 10 times more easily machined than predecessor 15Cr-5Ni alloys.

Carpenter Technology Corp. in Reading said it developed Project 7000 15Cr-5Ni stainless to be more easily machined than its predecessor, and thus to open opportunities to reduce part-making cycle time and costs for aircraft structural components, including rod end bearings and landing gear structure, and engine parts such as brackets.

Project 7000 is vacuum melted, chemically balanced, and processed to optimize its machinability in the solution-annealed as well as age-hardened conditions. According to Carpenter, metalworking plants that served as beta sites were able to increase their parts productivity by as much as 145 percent using Project 7000 stainless steel. Depending on the heat-treated condition of the material, Carpenter obtained improvements in machinability ranging from 3.5 to 10 times when machining the alloy in its own research and development screw machine facility in Reading.

In addition to being more easily machined, the Project 7000 alloy can be formed by cold working or forged. To prepare the steel for forging, the workpiece should be uniformly heated to about 2,000°F, and held at that temperature for one hour, according to a recommended schedule.

Industrial Galvanizers America Inc. of Chesterfield, Va, has purchased hot dip-galvanizing facilities in Miami and Columbia, S.C., to expand its operations in the southeastern states. The 40,000-square-foot Miami facility is the only hot dip-galvanizing plant in that city.

The Drew Marine division of Ashland Specialty Chemical Co. in Boonton, N.J., is supplying an AWT automated water treatment system to Royal Caribbean International's first Vantage class cruise ship under construction at Meyer Werft GmbH in Germany. The AWT system continuously monitors boiler water conditions and automatically doses chemical treatments to required levels for optimizing the performance of the steam generating equipment. Delivery will be made to GE Packaged Power of Houston.

Ballard Power Systems Inc. in Burnaby, British Columbia, unveiled its next-generation fuel cell stack, the Mark 900, in Detroit in January. The fuel cell stack is incorporated in the Ballard Mark 900 Series fuel cell power module, uses low-cost materials, and is designed for manufacturing in automotive volumes. Ballard claims that its Mark 900 module is more powerful and compact than proton exchange membranes shown publicly to date. It generates 75 kW of power and occupies half the space of Ballard's Mark 700 fuel cell.

Dobelle Institute of New York developed an artificial vision system for the blind. Its patient is able to read 2-inch letters from five feet away, representing a visual acuity of 20/400. The patient also negotiates New York's subways.

Engelhard Corp. of Iselin, N.J., is supplying certain Volvo sedans with radiator coatings that destroy smog while the cars are rolling. Engelhard reports as much as a 75 percent conversion of the ozone passing through the radiator to oxygen.

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