A335P91 alloy tube introduction
A335P91 alloy pipe is heat-resistant steel with pearlite structure. It has high thermal strength (δb≥440MPa) and oxidation resistance at high temperatures, and has certain hydrogen corrosion resistance. Since the steel contains high content of Cr, C and other alloying elements, the steel has an obvious hardening tendency and poor weldability. The following g indicates boiler steel.
The principle of hydrogen purification by A335P91 alloy tube
The principle of hydrogen purification by A335P91 alloy tube is that when the hydrogen to be purified is passed into one side of the A335P91 alloy tube at 300-500°C, the hydrogen is adsorbed on the wall of the 15crmog alloy tube. Since the 4d electron layer of palladium lacks two Electrons can form unstable chemical bonds with hydrogen (the reaction between palladium and hydrogen is reversible). Under the action of palladium, hydrogen is ionized into protons with a radius of 1.5×1015m, and the lattice constant of palladium is 3.88 ×10-10m (at 20℃), so it can pass through the A335P91 alloy tube. Under the action of palladium, the protons combine with the electrons and re-form hydrogen molecules, and escape from the other side of the 15crmog alloy tube. On the surface of 15crmog alloy tube, undissociated gas is impermeable, so A335P91 alloy tube can be used to obtain high-purity hydrogen. Although palladium has unique hydrogen permeability, pure palladium has poor mechanical properties, is easily oxidized at high temperatures, and has a low recrystallization temperature, which can easily deform and embrittle the A335P91 alloy tube, so pure palladium cannot be used as a permeable membrane.
A335P91 alloy tube temperature resistance
A335P91 alloy pipe 15CrMoG steel is a steel type widely used in the power industry. It has high thermal strength performance when used at 500℃-550℃. When the operating temperature is greater than 550°C, its thermal strength performance is significantly reduced. This steel is mainly used for high and medium pressure pipelines and steam guide pipes with steam parameters of 510°C, and heater pipes with pipe wall temperatures below 550°C.
What material is A335P91 alloy pipe 15CrMoG made of?
The microstructure of 15CrMoG and 15CrMo steel in the A335P91 alloy pipe in the normal supply state is ferrite plus pearlite. During the long-term operation of the A335P91 alloy pipe in the working temperature range of 500℃-550℃, pearlite spheroidization and alloying will occur. Due to the redistribution of elements between solid solution and carbide and the change of carbide phase structure, the thermal strength and mechanical properties of A335P91 alloy pipe gradually decrease as the degree of pearlite spheroidization and the degree of depletion of alloying elements in solid solution increase. As a result, the material gradually deteriorates or even fails.
What is the performance of A335P91 alloy pipe?
The performance of alloy pipes is much higher than that of ordinary seamless steel pipes, because this steel pipe contains more Cr, and its high temperature resistance, low temperature resistance, and corrosion resistance are unmatched by other seamless steel pipes, so alloy pipes are widely used in petroleum , aerospace, chemical industry, electric power, boiler, military industry and other industries are widely used. Common materials of alloy pipes are: 15CrMoG, 12CrMoG, P91, WB36.
