Influence of Continuous Casting Billet Surface Defects on Continuous Rolling Steel Pipe Surface Quality

Aimed to the defect problem on the surface of continuous rolling steel pipes, combining two rolling processes, the corresponding relationship between the billet defects and the finished product defects was researched by means of artificial wounding or keeping original defects of the billet surface, and how the billet defects influencing the surface quality of steel pipes was researched by metallographic analysis. The results show that the defects on the surface of continous casting billets will be reflected on the surface of the rolled steel pipes. Finally measures for avoiding defective billets entering into the later process in order to improve qualification rate of continuous rolling mills were discussed.