Redox reaction of smls pipe
The cs seamless pipe spark identification method is a method to judge its chemical composition by using the physical and chemical phenomena produced in the grinding process of steel. When the steel sample is ground on the grinding wheel, the abrasive grains are ejected along the tangential direction of the grinding wheel rotation. The abrasive grains are in a high temperature state, and the surface is strongly oxidized to form a layer of Fe0 film. The carbon in the cs seamless pipe is very easy to react with oxygen at high temperature, Fe0+C→Fe+C0, so that Fe0 is reduced; the reduced Fe will be oxidized again, and then reduced again.
This oxidation-reduction reaction proceeds cyclically, and CO gas is continuously produced. When the iron oxide film on the surface of the particle cannot control the CO gas produced, the phenomenon of bursting occurs and sparks are formed. If unreacted Fe and C remain in the particles after the explosion, the reaction will continue to occur, and there will be two, three or multiple explosion sparks.
The carbon in the cs seamless pipe is the basic element to form the spark. When steel contains manganese, silicon tungsten, chromium, molybdenum and other elements, their oxides will affect the lines, colors and states of sparks. According to the characteristics of the spark, the carbon content and other element content of the steel can be roughly judged.
The tissue properties of cs seamless pipe are not uniform after cold drawing.
Due to the inhomogeneity of the deformation of the cs seamless pipe during the cold drawing process, the degree of deformation is different from the outer surface layer to the inner surface layer. The additional bending deformation and additional shearing deformation near the outer surface layer are larger, so the total deformation degree of the outer layer is larger. It is larger than the inner layer, so the outer layer has finer grains and higher hardness, and the inner layer is the opposite. The thicker the pipe wall, the greater the coefficient of friction, the greater the cone angle of the mold, the greater the difference in the total deformation of the inner and outer layers, and the greater the inhomogeneity of structure and performance. After deformation, the tissue properties of the inner and outer layers are inconsistent.
