GZHCH Automatic CNC Duct Production Line is our latest coil line. With U-shaped structure, it reduces time of plate passing period which achieves the productivity of 20-25 seconds per piece. The design adopts the Duct Line III as the main brain, the Pittsburgh Seam after processing is in the front. When producing large-size duct, the short side bent first, which is more suitable for the seam closing.