Structural Steel Tube Supplier-GNEE
Carbon structural steel pipe (GB/8162-2008)
The content of other alloying elements brought into the steel by raw materials for carbon structural steel pipes, such as chromium, nickel and copper, generally does not exceed 0.30%. According to the composition and performance requirements, the grades of this type of structural steel pipes are Q195, Q215A, B, Q235A, B , C, D, Q255A, B, Q275 and other steel grades.
Note: "Q" is the Chinese pinyin capital of the word "Qu" for yield, and the following numbers are the minimum yield point (σs) value of the grade, and the following symbols are based on the impurity element (sulfur, phosphorus) content of the steel. From high to low and with changes in carbon and manganese elements, it is divided into four grades: A, B, C, and D.
This type of structural steel pipe has the largest output and is widely used. It is mostly rolled into plates, profiles (round, square, flat, machine, groove, angle, etc.) and special shapes, as well as manufacturing welded steel pipes. Mainly used in factory buildings, bridges, ships and other building structures and general pipelines for transporting fluids. This type of steel is generally used directly without heat treatment.
Low alloy high strength structural steel pipe (GB/T8162-2008)
In addition to a certain amount of basic elements such as silicon or manganese, this type of structural steel pipe also contains other elements suitable for my country's resource conditions. Trace elements such as vanadium (V), niobium (Nb), titanium (Ti), aluminum (Al), molybdenum (Mo), nitrogen (N), and rare earth (RE). According to chemical composition and performance requirements, its grades include Q295A, B, Q345A, B, C, D, E, Q390A, B, C, D, E, Q420A, B, C, D, E, Q460C, D, E, etc. The steel grade indicates that its meaning is the same as that of carbon structural steel pipes.
Fine grain trace elements such as V, Nb, Ti, Al, etc., in this type of structural steel pipes, in addition to A and B grade steel, the C, D and E grade steel should contain at least one of them; in order to improve the Performance, one of the A and B grade steels can also be added. In addition, the residual element content of Cr, Ni, and Cu in this type of steel is not more than 0.30%. Q345A, B, C, D, and E are representative grades of this type of steel. Among them, grade A and B steel are usually called 16Mn; structural steel pipes of grade C and above need to add more than one trace element, and add a low-temperature impact property to its mechanical properties.
This type of structural steel pipe is comparable to carbon structural steel. It has the advantages of high strength, good comprehensive performance, long service life, wide range of applications, and relatively economical performance. This steel is often rolled into plates, profiles, seamless steel pipes, etc., and is widely used in bridges, ships, boilers, vehicles and important building structures.
