Large industrial processes require to transport large volume of hot air and flue gases in controlled manner between process equipments through a series of ducts system. Large rectangular duct structural system for an industrial process. The duct structural system associated with industrial applications are significantly large and in some ways unique structures. Though ducts having circular or rectangular cross sections are feasible, the large industrial ducts are often rectangular. The cross sectional dimensions of such industrial ducts may be in the range of 5m to 15m, sometimes even larger. Industrial duct during fabrication. The large rectangular ducts are air tight conduits to transport air or flue gases under positive or negative pressure. The ducts are sometimes exposed to high temperature as well as the air or flue gases are transported at elevated temperature. In order to accommodate the expansion due to the temperature, expansions joints are introduced along the duct length. This creates independent pieces of ducts with own floating supports. Typical piece of large rectangular duct between two expansion joints.
