热轧无缝钢管外表面青线的产生与控制研究OA

Addressing the outer surface roll trace defect of the hot-rolled seamless steel pipe,the causes are identi-fied by means of analyzing the key factors in the stretch reducing process as may lead to occurrence of the said defect,including roll quality,mill stand assembly,and pass configuration etc.Accordingly relevant countermeasures are worked out.It is revealed via the analysis that the surface roll trace primarily is caused by abnormal deformation of the tube at the stretch reducing roll surface or in the roll gap.Furthermore,inadequate roll performance or improper pass configuration can induce abnormal roll wear and crack,which also contribute to the formation of the surface roll trace.So it is suggested to effectively prevent the occurrence of the said defect via improvements associated with such aspects as stretch reducing roll quality,mill stand assembly accuracy,alignment precision of the rolling center line,and the pass configuration.