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 NITROGEN GENERATORSNitrogen generators use either membrane or pressure-swing-adsorption (PSA) technologies. Membrane generators made by Balston, a division of Parker, produce up to 99.5% pure, commercially sterile nitrogen at dewpoints to -58[degrees]F from compressed air. They use proprietary membrane-separation technology to divide air into two streams: one 95 to 99.5% pure nitrogen, the other automotivegasaircompressor oxygen-rich with carbon dioxide and automotivegasaircompressor other trace gases.Compressed air flows through bundles of individual, hollow fibers made of semipermeable membranes. Each fiber has a perfectly circular cross section and a uniform bore automotivegasaircompressor through its center. Because the fibers are so small, a great many can be packed into a limited space, providing enough surface area to produce a relatively high-volume flow of nitrogen. With the integration of the motor, VSD, and magnetic-bearing system, the capacitors required for the motor and drive can be used as a backup power source for the bearings in the event of a power outage or emergency shutdown.CAPACITY AND EFFICIENCYAmong the key parameters affecting performance are capacity (tons) and efficiency (kilowatts per ton). The compressor''s capacity ranges from 60 to 90 tons, depending on the operating conditions. Plans call for that range to be extended to 150 tons water-cooled and 115 tons air-cooled by the end of 2004 with the use of R-134a refrigerant. An R-22 version is planned for retrofit applications.Efficiency improvements stem from a combination of the centrifugal compressor, permanent-magnet motor, and magnetic bearings. Within the compressor, efficiency is affected by the compressor isentropic efficiency (the efficiency of the wheels), the motor, and the bearings. Traditional induction motors of this size typically are in the 92-percent efficiency range. This compressor''s permanent-magnet motor has an efficiency of 96 to 97 percent. Efficiency is further enhanced automotivegasaircompressor and automotivegasaircompressor with the use of magnetic bearings, which avoid fire friction of rubbing parts associated with traditional oiled bearings. Conventional bearings can use as much as 10,000 w, while magnetic bearings require only 180 w. That amounts to 500 times less friction loss. Current development projects are expanding the range and duty of the compressor wheels and promise to offer even greater efficiency for water-cooled and air-cooled duties and different capacities.CONTROLSThe new compressor effectively is a computer. It provides diagnostic and performance information through Modbus to the refrigeration system, which then communicates to the building automation system through Modbus, LonWorks, or BACnet.CHILLER APPLICATIONThe compressor manufacturer and a major chiller manufacturer teamed up automotivegasaircompressor to develop a line of ARI-certified water-cooled chillers, which were expected to be introduced in January 2004. The combination of flooded-evaporator technology and an oil-free system has allowed very close approaches and, subsequently, enhanced performance. The integrated VFD allows excellent part-load performance as power consumption drops off, depending on the head relief, near the cube root of the shaft speed. Buy a gas air compressor with us and save a TON of cash. Our selection of cheap gas air compressors is second to none.
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