Manufacturing process requirements:

① The manufacture of rectangular straight pipes must be stopped on the dedicated import assembly line to ensure the manufacturing accuracy and airtightness of air ducts.

② The blanking of rectangular air duct fittings shall be completed automatically by using computer software on the imported special machine, and the automatic plasma cutting process shall be completed on the imported special plasma cutting machine for sheet metal.

③ The seam connection of rectangular air duct shall adopt the imported automatic occluder to stop the occluding process.

④ The connection between the rectangular air duct body and the plug-in flange shall adopt the rivetless connection process, and the imported equipment shall be used to stop the rivetless connection process.

⑤ The connecting flange of rectangular air duct shall adopt the connecting process of connecting plate flange and plug-in flange. When the length of the large side of the air duct is less than or equal to 2000mm, the connecting method of common plate flange shall be adopted. When the length of the large side of the air duct is more than 2000mm and less than or equal to 2500mm, the connecting method of plug-in flange shall be adopted. The rectangular air duct shall be mechanically pressed with stiffeners, and the spacing of stiffeners shall be about 300mm.