12Cr1MoVG alloy steel tube is based on high-quality carbon structural steel, appropriately join one or several alloy elements, to improve the mechanical properties of steel, toughness and hardenability. The products made of 12Cr1MoVG are usually subjected to heat treatment (normalizing or quenching and tempering); The parts made by 12Cr1MoVG are usually subjected to quenching or surface chemical treatment (carburizing, nitriding, etc.) before use, Quenching or high-frequency quenching and other treatment. Therefore, according to the chemical composition (mainly carbon content), heat treatment process and the use of different, such steel can be divided into carburizing, quenching and tempering and nitrogen steel.