VERTICAL HOT-WATER FIRE-TUBE BOILER Russian patent published in 2000 - IPC

FIELD: heating and hot water supply systems. SUBSTANCE: proposed boiler has shell with furnace and burner unit arranged in its lower portion; boiler is also provided with supply and return branch pipes and flue gas discharge branch pipe. Upper portion of boiler is made in form of central tubular and ring-shaped chambers whose lower parts are blanked off and upper parts are connected with boiler shell. Chambers form inner and outer ring-shaped vertical gas duct with inner diameter of shell. Inner gas duct is connected with outer gas duct and with flue gas discharge branch pipe by means of port; inner and outer surfaces of gas ducts are made in form of cylindrical helical metal fins forming helical uptake gas duct. EFFECT: enhanced efficiency; low cost of generation of thermal energy. 1 dwg