GB/T 11251 alloy steel is one of the common hot-rolled alloy structural steels. This steel coil is widely used in various applications in bearings/gears of rotating machinery.

API Spec 5L is an international standard that specifies the manufacturing requirements for two product specification grades (PSL 1 and PSL 2) of seamless and welded steel pipes used in pipeline transportation systems in the oil and gas industry.

EN 10083-3 steel is an alloy steel used for quenching and tempering. This standard regulates the technical delivery conditions of alloy steels. 

A588 alloy structural steel coil is made of a kind of weather-resistant steel, and its material standard is ASTM A588/A588M. It is a type of low-alloy high-strength structural steel and is mainly used for structural components in outdoor exposure environments, such as bridges, large containers, chimneys, etc..

JIS G3103 boiler vessel coil is a carbon steel and molybdenum alloy steel hot rolled coil for Chinese and high temperature boilers and pressure vessels. The main grades of JIS G3103 boiler vessel steel are: SB410, SB450, SB480,SB450M and SB480M.

DIN 17155 pressure vessel steel coil is made of steel for boilers and pressure vessels. In addition to boilers and pressure vessels, DIN 17155 pressure vessel steel is also used to manufacture high-temperature liquid delivery pipes.

A537 pressure vessel steel coil is made of heat treated carbon manganese silicon steel that is used in pressure vessel fabrication. There are 3 grades, which are Grade 1, Grade 2, and Grade 3.

A533 pressure vessel steel coil is made of manganese-molybdenum-nickel alloy steel that is suitable for welding pressure vessels. There are three levels of level 1, level 2 and level 3.

A516 vessel steel coil is made of a high-quality boiler and pressure vessel steel that is very suitable for low to medium temperature applications. 

A515 is the same as ASME SA-515 and is the standard specification for welding carbon steel for high temperature service in boilers and other pressure vessels.