文中对圆柱相贯线的两面角、焊接坡口角及度量平面首次提出了定义。建立了两管斜交和正交情况下在支轴剖面和法剖面中的两面角和坡口角的计算式。文中还提出用切割炬矢来表示切割炬恣态角的概念,并为机械式和数控管切割机的设计提出了具体建议,该文首次用矢量法分析坡口角问题,使问题的分析比较简捷。 The paper first proposed the definition of the two-sided corner, the welding bevel angle and the metric plane of the intersecting line of the cylinder. The formulas for calculating the dihedral angle and the bevel angle in the cross-section and the normal section of the support under two oblique and orthogonal conditions are established. In this paper, the concept of using cutting torch to represent the corner of cutting torch is also proposed. Some suggestions are put forward for the design of mechanical and numerical control pipe cutting machine. The paper analyzes the bevel angle with vector method for the first time, which makes the analysis of the problem relatively simple.