Spiral duct machine, is the production of spiral duct machine. Spiral ducts, also known as spiral biting thin-walled tube, first applied to the western countries of the military industry, such as warships, ship row (send) wind system, and later used for trains, subways, mines and other civilian facilities. By 2000, according to statistics, the United States office, shopping malls, subway and other applications of spiral duct has reached 95.6%, residential residential central air conditioning applications spiral duct also reached 72.5%.