OVERFIRE AIR TUBE DAMPER FOR BOILER AND METHOD FOR REGULATING OVERFIRE AIR

摘要

A damper (60) and overfire air duct (54) in a combustion system (10) having a combustion structure defining a flue gas passage (14), the damper and overfi re air duct comprising: an inlet (58) to the overfire air duct and an outlet to the duct discharging overfire air into the flue gas passage, and the damper (60) aligned with an axis of the overfire air duct (54), and having an open position (60) axially distal to the inlet and a closed position (60a) at least partially in the inlet and duct, wherein the damper is movable axially between the open and closed positions.