Air ducts and ventilation systems components are manufactured in accordance with design drawings, standards and specifications. Ducts of black and galvanized steel sheet hot-rolled (cold) diameter or larger in size by up to 2000 mm inclusive. produce spiral-welded or key-in rebate, spiral-welded or welded to the welding, and air ducts having a diameter or size greater by more 2000 mm – panel (welded, kleesvarnymi). Ducts of metal-made to fold, and stainless steel, titanium and its alloys, aluminum sheet metal and its alloys – for welding or seam. Flexible ducting made of aluminum and steel.

In the manufacture of welded duct with a longitudinal flare should be applied suture welding. Ducts are made of two classes: P – dense, H – normal. Sheet metal thickness of less than 1.5 mm should be welded lap, and a thickness of 1.5 to 2 mm – butt or lap. Sheet metal thickness greater than 2 mm shall be welded back to back. For welded joints and fittings and straight sections parts of the duct, made from black steel sheet hot-rolled (cold) and stainless steel, the following welding methods: – plasma – automatic and semi-automatic arc under layer of flux or inert gas – contact – roller – MMA.

For welding ducts made from sheet aluminum and its alloys, it should apply the following welding methods: – TIG automatic – consumable electrode – TIG manual – non-consumable electrode with the filler wire – gas. For welding ducts made of titanium and its alloys are used TIG welding consumable electrode. Ducts made of sheet aluminum and its alloys with thickness up to 1.5 mm should izgotav-Lebanon in rebate. The longitudinal folds of sheet metal ducts in the roof and stainless steel and aluminum sheet with a diameter or greater in size by 500 mm or more should be fixed at the beginning and end of the link duct spot welding, rivets.