GB5310 is the standard code of China's national standard "Seamless Steel Pipes for High-Pressure Boilers", which specifies the technical requirements for seamless steel pipes for high-pressure boilers and steam pipes. The GB5310 standard covers a variety of steel grades to meet different application needs. The following are some common grades and their application industries:

20G: 20G is one of the most widely used grades in GB5310, with the main components of carbon, manganese and silicon. It has good comprehensive mechanical properties and welding properties, and is mainly used to manufacture key components such as water-cooled walls, superheaters, economizers and drums in power station boilers.

15CrMoG: This steel contains chromium and molybdenum, and has high high-temperature strength and oxidation resistance. 15CrMoG seamless steel pipes are often used to manufacture high-temperature and high-pressure steam pipes, headers and conduits, etc., and are widely used in petrochemical and power industries.

12Cr1MoVG: Contains high chromium, molybdenum and vanadium elements, with excellent high-temperature performance and long-term stability. Seamless steel pipes of this grade are often used in high-temperature and high-pressure boilers and nuclear power equipment, especially heat exchangers, steam pipes, etc.

These different grades of seamless steel pipes are widely used in the manufacture of key components in high-temperature and high-pressure environments such as power, petrochemical, and nuclear power due to their unique chemical composition and mechanical properties. By selecting the right steel grade, the safety and stability of the equipment under extreme working conditions can be guaranteed, and the service life can be extended.