中文摘要：

我国小直径无缝钢管主要采用穿孔＋冷轧（拔）工艺生产。该方式能耗高、成材率低、酸洗污染严重,因此必须研究热轧工艺以替代冷加工工艺。本文针对短流程热轧小直径无缝管的宽展变形问题,以相似孔型为纽带,通过解析得出了小直径无缝管的宽展特性。并对φ50 mm×4 mm的毛管进行了三机架连轧实验,验证了宽展对轧制结果的影响。最后针对宽展特性的孔型改进方法进行了讨论,结果能为小直径无缝管的孔型工艺参数设计提供参考。

英文摘要：

The main production method of minor diameter seamless steel pipes in China is piercing ＋cold rolling （drawing） process. This method is high energy consumption, low yield and serious acid washing pollution. Therefore, it is necessary to research hot rolling process to replace the cold working process. Aiming at the width deformation problem of small diameter seamless pipe by short process hot rolling, taking the similar pass as the ligament, the characteristic of width deformation of minor diameter seamless pipe is obtained by analytical approach. And the three stand continuous rolling experiment of φ50 mm×4 mm blank tube was carried out. The effect of the spread on rolling results was verified. Finally, the improved method of pass based on the tube width deformation was discussed. The results can provide reference for the design of pass process parameters of small diameter seamless pipe.