This steel plate duct work system, weighing 150 tons, was made up of gas flow spaces up to 33’ wide and a max of 9’-2 deep that included interfaces at the Boiler Outlet, Filter Fabric House Inlet and Outlet, Dual ID Fan Inlet, Fan Outlet, and Stack Inlet. The duct work included flat and rolled plate, stiffened externally by hot rolled shapes and supported internally in some areas by round HSS truss configurations. The project also included recirculation inlet and outlet legs with inline damper. Internal rolled plate turning vanes were utilized for directional gas flow. The duct work was designed for thermal expansion/contraction of up to a 600 deg F excursion temperature and therefore included expansion joints throughout. Other design features included structural support slide plates, test ports, maintenance/inspection access doors, lifting lugs, and duct supported access walkway.
