TDFAs a type of fast flange air duct technology, the process has been widely promoted in Europe. It combines the advantages of angle steel flange air ducts, with stronger structural strength, no welding or riveting, fully galvanized sheet manufacturing, good corrosion resistance, tight connection, and low air leakage rate. The finished product of the air duct has a beautiful appearance, accurate dimensions, smooth contour lines, and air leakage far below the national standard. Beneficial for the production of ventilation ducts to be industrialized, scaled up, standardized, and automated.