热轧无缝钢管内折缺陷分析

热轧无缝钢管的内折缺陷一直是影响钢管一次合格率和成材率指标的主要原因之一。内折缺陷主要在穿孔过程中产生,其产生的主要原因与连铸管坯质量（内因）有关,也与穿孔工艺制度（外因）合理与否有关。主要分析了穿孔工艺制度与内折的关系,并提出了预防措施。

Analysis of Internal Fold of Hot-rolled Seamless Steel Pipe

The defect of internal fold of the hot-rolled seamless steel pipe has been so far one of the major elements which negatively influences the first qualification rate and yield target of steel pipes. The said defect mainly occurs in the piercing process,and the main causes for it are related to both the quality of the continuously-cast billet (the internal cause) and the reasonability of the piercing schedule (the external cause). The analysis focuses on the relationship between the rolling process schedule a...