The is the economic type welding machine for thin plate, as attachment for air duct. Seam welding machine,seaming welder,welding machine,stitch welding 1. Cross seam / longitudinal seam welding;2. Quick welding speed and high efficient3. Continuous weld and pulse weld can be set on the machine;4. Welding speed can be regulated continuously.5. Suitable for welding airproof vessels.