BOILER STRUCTURE

摘要

A boiler structure capable of reducing the power of auxiliary devices such as a feed water pump and improving the flow stability and the natural circulating characteristic by so reducing the pressure loss of boiler evaporation tubes as to match a thermal load which changes depending on the distance in a boiler height direction.  In the boiler structure, the large number of boiler evaporation tubes disposed on the wall surface of a furnace (2) form a furnace water-cooling screen (4), and the water force-fed to the boiler evaporation tubes is heated in the furnace (2) when flowing through the insides of the tubes, and steam is generated.  Multiple types of boiler evaporation tubes connected in the boiler structure have respective wall thicknesses adjusted according to the thermal load of the furnace and respective inner diameters further reduced in the areas where the thermal load of the furnace is larger.