Features of boiler tube

High-pressure boiler tube is a type of boiler tube, which belongs to the seamless tube type. The manufacturing method is the same as that of seamless steel tube high-pressure boiler tube, but there are strict regulations on the alloy structural steel commonly used in the production of seamless steel tube. High-pressure boiler tubes are often in high-temperature and high-pressure applications. High-pressure boiler tubes are mainly used to produce superheater tubes, reheater tubes, bronchial tubes, main pipes, etc. for high-pressure and ultra-high-pressure heating furnaces.

Due to the long-term operation of the seamless carbon steel boiler tubes under high temperature and high pressure standards, the raw materials will experience creep, plastic deformation and ductility reduction, the initial mechanism changes, and corrosion will occur. The seamless steel pipe used as a heating furnace should have:

①Long-term compressive strength;

②Working ability of plastic deformation;

③The least time-sensitive tendency and hot ductility;

④High oxidation resistance, coal ash resistance, corrosion resistance at high temperature of gas, steam and stress corrosion characteristics;

⑤Excellent mechanism reliability and excellent performance.

The alloy structural steel of the high-pressure boiler tube includes alloy steel and its ferrite, metallographic structure and martensitic stainless steel heat-resistant steel. In order to improve the thermal efficiency of thermal power generating units and reduce fuel consumption, all countries are dominated by the development trend of capacity, high main parameters (high temperature, high pressure) thermal power plant generating units (around 1500MW). The working pressure of steam is increased to 31.5～34.3MPa, and the temperature of superheated steam reaches 595～700℃, which is a trend toward ultra-high pressure critical pressure, which clearly puts forward higher regulations for high-pressure boiler tubes. Therefore, a new alloy structural steel was developed and designed.