Duct production line II is on the basis of the production line for type I add the cutting unit is used for air duct, this production line is composed of a decoiler, leveler & grooving unit, “V” and “口” notching unit, cutting unit composition. The standard configuration the “V” and “口” notching unit make for TDF flange duct, thereinto the “口” notching unit can also be used to produce TDC flange. Electrical control with full servo control, the control system has a closed-loop feedback system, high precision and stability. The maximum operating speed of 16 m / min. Length tolerance is ± 0.5mm, diagonal error ± 0.8mm.