Quality carbon structural steel pipe, which is a carbon structure steel pipe.
In addition to steel containing carbon (C) element and a certain amount of
deoxidized silicon (a Si) (generally not more than 0.40%), manganese (of Mn)
(generally not more than 0.80%, to 1.20% may be higher) alloying elements
outside, without other alloying elements (except residual elements). Such steel
must also ensure that the chemical composition and mechanical properties. Sulfur
(S), phosphorus (P) the general control of impurity elements 0.035% or less. The
material is high-quality carbon structural steel (GB / T699-1999) standard
material. Quality carbon structural steel (GB / T699-1999)
Steel Classification
Such adjustment is to rely on the carbon steel (C) the amount to improve the mechanical properties of steel, therefore, based on the level of carbon content, these steels can be divided into:
Low carbon steel - carbon content generally less than 0.25%, such as steel, 10,20;
Carbon steel - carbon content is generally between 0.25 to 0.60%, such as steel, 35,45;
High-carbon steel - carbon content is generally greater than 0.60%. Such is generally not used in the manufacture of steel pipe.
In fact, the carbon content between them and no clear boundaries. Such a large steel production, uses a wider, and more generally rolling (forging) is made round, square, flat and other sections, plates and seamless steel tubes. Mainly for the manufacture of general structural and mechanical structure parts and components and architectural structures and transmission fluid pipes. According to requirements, and sometimes you need to heat treatment (normalizing or quenching and tempering) after use.
Quality carbon structural steel is made of carbon steel (GB / T699-1999) standard material.
The main material of high-quality carbon structural steel pipe: Q195, Q215A, B, Q235A, B, C, D, Q255A, B, Q275
Technical standard
If controlled 0.030% or less are called high quality steel, behind grade should be added to "A", such as 20A; if P control 0.025%, S controlled 0.020% or less, called premium quality steel, behind grade should be added "E" to show the difference. For raw materials into steel by the remnants of other alloying elements such as chromium (Cr), Nickel (Ni), copper (Cu), etc. The content of the general control Cr≤0.25%, Ni≤0.30%, Cu≤0.25%. Some grades of manganese (Mn) content of 1.40%, manganese known.
