Air ducts of rectangular cut (rectangular air ducts)
Rectangular air ducts should have a ratio of sides to no more than 6.3.
Air ducts of a rectangular cut, in which the air is moving at a temperature below 80°C, must be made of sheet steel of a thickness of not more than:
– Rectangular air ducts with a larger side of size less than 250 mm – 0.5 mm
– Rectangular air ducts with a larger side of size from 300 to 1000 mm – 0.7 mm
– Rectangular air ducts with a larger side of size from 1250 to +2000 mm – 0,9 mm
The rectangular air ducts are interconnected between them and with the shaped wares by means of previously filled flanges on their ends or a rail connection. The rail connection due to the great complexity of its manufacturing is used rarer. The flanges are currently made from special mounting profiles and angles of appropriate sizes. Pressurizing between flanges of air ducts is carried out with the help of a special sealant glued to one of the adjacent flanges. Air ducts of a rectangular section are convenient to use wherein by virtue of different reasons, there is a limit on the height of the filing ceiling.