电站锅炉结构（Utility boiler structure）.doc

电站锅炉结构（Utility boiler structure） in Small subscription Utility boilers produce superheated steam to drive steam turbines. According to the cycle mode, the utility boiler can be divided into a natural circulation power station boiler, a plurality of forced circulation power station boilers, a power station direct current boiler and a compound circulating boiler. Section 1 Structure of natural circulation boiler The natural circulation boiler establishes the circulation of the working fluid by using the density difference between the mixture of water and steam in the rising pipe of the circulating circuit and the water in the downcomer. The utility model is characterized in that the utility model has a boiler barrel and can work only under the critical pressure. The circulation and return circuit of the natural circulation boiler is composed of a boiler barrel, a header, a downcomer and an ascending pipe. The falling pipe is arranged outside the furnace wall and is not heated, and the upper end is connected with the boiler barrel, so that the inner pipe of the boiler barrel flows into the pipe, and the lower end is connected with the header. Also known as the rising tube water wall tube, is arranged in the furnace flame around and absorb radiant heat, so that by the lower header into the water vaporization riser to produce steam pipe down. The rising tube and set top box is connected with the drum, connected to the steam water mixture generated inside the tube to tube were separated in the wok, the drum, after the separation of the water into the downcomer, saturated steam superheater into further heating. In a natural circulation boiler, the boiler barrel is the fixed dividing point between the evaporating heat, the heating surface and the superheater. The quality of the drum, the consumption of metal, manufacturing, transportation and installation are more difficult, because of the large cylinder wall temperature tube wall is thick and is limited by the boiler stop