Stainless steel pipe internal components

- Mar 06, 2018-

Stainless steel pipe internal components

Stainless steel pipe fittings (flanges) of the internal composition of complex elements, there are five main types of these five elements are on the performance of stainless steel pipe fittings play a decisive influence, beneficial or harmful depends on how you pinch the content. In addition to this major element, there are other trace elements, such as Cr, Ni, etc., but these trace elements will have some impact on the performance of stainless steel pipe, it should also be strictly controlled.


(1) The performance of carbon steel depends mainly on the carbon content. Steel carbon content increases, the steel strength and hardness value increases while the plasticity and toughness will be reduced.

(2) In silicon cast carbon steel, the mass fraction of silicon is 0.2% -0.45%. The content of this range has little effect on the mechanical properties. Require a certain amount of silicon is to ensure the deoxidation of steel, therefore, silicon is a beneficial element in the steel.

(3) sulfur and sulfur in steel is a harmful element, which is mainly in the form of Fey steel exists. The formation of eutectic with iron, the melting point of 989 degrees, much lower than the melting point of steel. In the solidification process of steel, sulfide often precipitation in the steel grain boundaries, because of its low strength, brittleness, greatly reducing the mechanical properties of steel and prone to hot brittle phenomenon at high temperatures. If the molten steel deoxidation is not good, containing more FeC, the sulfide and Fe0 form ternary eutectic, the lower melting point (about 940 degrees), more harmful. Sulfur also adversely affects the weldability of steel. Therefore, we should try to remove sulfur in steelmaking.

(4) manganese and manganese in the casting of stainless steel pipe, manganese required mass fraction of 0.5% -0.8%, its role is deoxygenation, desulfurization.

(5) Phosphorus is also harmful impurities in steel, hope the smaller the better, requiring its mass fraction of less than 0.06%.