Boiler structure

Abstract

A boiler structure that allows for an appropriate flow-rate distribution of an internal fluid to multiple divided furnace wall surfaces (water-wall) without excessive pressure loss so as to reduce the pressure loss (friction loss) occurring between furnace inlet headers and outlet headers is provided. In a boiler structure having a furnace water-wall ( 4 ) formed of multiple boiler evaporation tubes ( 3 ) disposed on a wall surface of a furnace and configured to generate steam by heating water inside the furnace when the water pressure-fed to the boiler evaporation tubes ( 3 ) flows inside the tubes, the boiler structure includes orifices ( 22 ), for an internal fluid, provided in inlet connection tubes ( 20 ) that guide the water to inlet headers ( 21 ) of furnace walls obtained by dividing the furnace water-wall ( 4 ) into multiple parts, and orifices ( 23 ) provided in nozzle stubs that guide the water from the inlet headers ( 21 ) to the boiler evaporation tubes ( 3 ).

1 . A boiler structure having a furnace water-wall formed of multiple boiler evaporation tubes disposed on a wall surface of a furnace and configured to generate steam by heating water inside the furnace when the water pressure-fed to the boiler evaporation tubes flows inside the tubes, the boiler structure comprising:
 first pressure-loss adjusting sections, for an internal fluid, provided in distribution tubes that guide the water to inlet headers of furnace walls obtained by dividing the furnace water-wall into multiple parts, and second pressure-loss adjusting sections provided in nozzle stubs that guide the water from the inlet headers to the boiler evaporation tubes.   
     
     
         2 . The boiler structure according to  claim 1 , wherein the first pressure-loss adjusting sections are configured by using one of or combining a plurality of fixed orifices fitted in the distribution tubes, thick-walled short tubes having the same outer diameter as the distribution tubes and fitted therein, and individual adjustment of a pressure loss occurring in the distribution tubes.