High pressure boiler tube is one of the boiler tube, belonging to the seamless steel tube category.Manufacturing methods and seamless tube are the same, but have strict request for manufacturing steel used in the steel.
High pressure boiler tubes are often in high temperature and high pressure conditions,
when using the pipe under the action of high temperature flue gas and water vapor, oxidation and corrosion will happen. Requirements of steel pipe with high rupture strength, high oxidation corrosion resistance, and have good organizational stability. High pressure boiler tube is mainly used to manufacture high-pressure and ultrahigh-pressure boiler superheater tubes, reheater tube, airway, such as main steam pipe. High pressure boiler tubes are often in high temperature and high pressure conditions, when using the pipe under the action of high temperature flue gas and water vapor, oxidation and corrosion will happen.Requirements of
seamless steel pipe with high rupture strength, high oxidation corrosion resistance, and have good organizational stability.High pressure boiler tube is mainly used to manufacture high-pressure and ultrahigh-pressure boiler superheater tubes, reheater tube, airway, such as main steam pipe.
High-pressure boiler tubes clear depth. Affect the results of unsaturated resin; chlorinated unsaturated polyester resin with a high degree of stability, excellent high-temperature oxidizing acids and wet chlorine and other oxidizing medium, outstanding resistance to chlorine solution medium and heat resistance, higher order under pressure to use, often regarded heating surface tube design is very thick. Clear depth of the high-pressure boiler tubes shall not exceed the nominal wall thickness of the negative bias, its clean-up of the actual wall thickness of the wall thickness shall not be less than the minimum allowed. Prevent high-pressure boiler in the fire rapidly warming deformed slump, its measures are varied, the key is to take a different approach depending on the circumstances, such as the use of insulation, refractory steel barrier direct flame burning, reduce the speed of heat transfer delayed steel temperature, strength becomes weak time.
But no matter what method adopted, the principle is the same. Fire retardant coating is a fire in recent years more advanced technical measures. Because of impurity elements affect the quality of the high-pressure boiler, high levels of harmful elements in steel products and inclusion of control has very strict requirements, to try various impurity elements are required to control at very low levels, often in production using secondary refining the production process in order to protect its cleanliness. First, high-pressure boiler pipe installation is difficult, especially in Supercritical no drum, increasing the starting system, heating pipe systems, rigid beam volume than conventional subcritical boilers large, quantity, and all the heating surface welding, installation difficult. Often in high-pressure boiler tubes when using high temperature and pressure conditions, the pipe under the action of high temperature gas and water vapor, oxidation and corrosion will occur. Boiler heating surface tubes running cooling conditions worsen, dry, so that a sudden increase in the short term wall temperature, the temperature reaches a critical point (Ac1) above, a sharp decline in the tensile strength of high pressure boiler tube, pipe stress exceeds the yield limit, resulting in shear fracture and burst pipes, burst pipes called this short burst overtemperature.
