Abstract: The connecting plate duct assemblies which form the inlet and outlet ducts for a rotary regenerative air preheater have a horizontal flange plate around the periphery. The vertical panels which house the rotor sit on the lower horizontal flange plate and are attached to lower vertical attachment bars extending up from the lower horizontal flange plate. The upper ends of the vertical housing panels are spaced below the upper horizontal flange plate and abut upper vertical attachment bars extending down from the upper horizontal flange plate. The upper ends of the vertical housing panels are welded to these upper vertical attachment bars to hold them in position and to seal the space. Sealing means are provided between the vertical housing panels and the rotor at both the upper and lower ends.

Abstract: The rotor for a rotary regenerative air preheater is fabricated from a combination of shop assembled rotor sector modules and field assembled components so as to eliminate the double plate diaphragms of conventional modular rotors. The shop assembled modules comprise one or more sectors and the field assembled components fit between the spaced shop assembled modules spaced around the rotor hub. The support gratings between the diaphragm plates support modular heat exchange baskets which are loaded into the rotor radially from the periphery.