半浮动芯棒连轧荒管壁厚不均的原因分析

Investigation of Causes Responsible for Wall Thickness Tolerance of Shell as Hot-rolled with Semi-floating Mandrel Mill

介绍了半浮动芯棒连轧管机荒管壁厚不均的类型及特点,荒管壁厚不均有同批壁厚不均、纵向壁厚不均和横向壁厚不均等3种类型。分析了荒管壁厚不均产生的原因,穿孔毛管壁厚不均、连轧管机孔型形状变化、轧制中心线偏移均会造成荒管横向壁厚不均;芯棒尺寸波动会引起荒管纵向壁厚不均和同批壁厚差。提出了改善半浮动芯棒连轧荒管壁厚不均的有效措施。

As for wall thickness unevenness of the shell produced with the semi-floating mandrel mill, there could be such different types as batch wall thickness unevenness, shall longitudinal wall thickness unevenness and transversal wall thickness unevenness. The causes for shell wall thickness unevenness are identified. Transversal wall thickness unevenness is due to the original wall thickness unevenness of the pierced hollow bloom, some change of the mandrel mill roll groove and deviation of the rolling centerline, while longitudinal wall thickness unevenness and batch wall thickness unevenness are due to geometric inconsistency of the mandrel. Countermeasures are proposed, accordingly.