Sufficient margin is added to the gas flow rate estimated from the boiler manufacturer's predicted MCR heat input so that the ID fans can handle the gas flow at the maximum demonstrated heat input without difficulty. Additional margins are provided for increased air leakages, boiler gas path fouling, air-heater fouling, fan performance deterioration, and other uncertainties. Some fans are specified to be designed for initial base load operation with provisions for future cyclical duty. Additional revised design conditions due to scrubber and balanced draft conversion affect the ID fan size. This sets the stage for two-speed conditions.
Static pressure varies as the speed squared.
HP varies as the speed cubed. Advantages of PAM 2. Speed Switching 5. Click Here to Bookmark the TECO-Westinghouse Motor Company Web Site. TECO-Westinghouse Motor Company.