15CrMoG high-pressure alloy tube

15CrMoG high-pressure alloy tube

15CrMoG high-pressure alloy tube is a steel widely used in the electric power industry. It has high thermal strength when used at 500℃-550℃. When the operating temperature is higher than 550 °C, its thermal strength performance is significantly reduced. Usually 15CrMo steel is mainly used for high and medium pressure pipes and steam guide pipes with steam parameters of 510 °C, and heat exchanger tubes with a tube wall temperature of 550 °C.

The same type of steel in foreign countries includes 15XM from the former Soviet Union, American grades T12, P12, Japanese grades STBA22, STPA22 and German grade 13CrMo44.

The microstructure of 15CrMo steel in the normal supply state is ferrite and pearlite. During the long-term operation of 15CrMo steel in the working temperature range of 500℃-550℃, spheroidization of pearlite and alloying elements between solid solution and carbide will occur. The redistribution of 15CrMo steel and the change of carbide phase structure, the thermal strength and mechanical properties of 15CrMo steel gradually decrease with the increase of the degree of pearlite spheroidization and the degree of depletion of alloying elements in solid solution, so that the material gradually deteriorates or even fails. Therefore, the degree of pearlite spheroidization in the microstructure of 15CrMo steel has been widely used as one of the important criteria for judging the reliability of this type of steel for a long time.