Research On Application Of Dynamic Soft Reduction Technology For Medium And Thin And Slab Continuous Caster

The center porosity and center segregation due to solidifying and contraction of molten steel in the continuous casting, its reduce the internal quality and processing performance of casting blank. The technology of dynamic soft reduction on the elimination or improvement of the centre porosity and centre segregation during the casting.This study researched application state of dynamic soft reduction in a Steel-making Plant, analysed the fundamental principle and development of soft reduction technology and the method of defining main parameter, researched the conformation of the conticaste,the operating principle and regulating method of SMART sector, checked the assay casting blank, evaluated the application result of dynamic soft reduction according to compare the casting blank's quality with another conticaster without soft reduction facility in the plant; A series of experiments for optimizing process parameters of X70 pipeline steel's soft reduction is carried out.The results are as follows: The technique of dynamic soft reduction displays important effects in lowing centre porosity, centre segregation and increasing internal quality, product nature; The maximum negative segregation generate±5mm range of maximum positive segregation's bilateral. The grade of maximum negative segregation is smaller than maximum negative segregation; In order to further increase the quality of casting blank, the position of reduction should adjust present f_s=0.2～0.1 to f_s =0.5～0.8; Thecenter segregation will increase when the pulling rate enlarges; The geometrical center isn't quite equate metallurgy center due to different side cooling velocity of inward and external arc in the direction of pipeline steel's thickness. the metallurgy center present in the region, which deviate 1mm to external arc of geometrical center.