In this paper, we propose a method of forming a tube into an oblique/curved shape by synchronous multipass spinning, in which the forming roller reciprocates in the radial direction in synchrony with the rotation angle of the spindle while the roller moves back and forth along the workpiece in the axial direction to gradually deform a blank tube into a target shape. The target oblique/curved shape is expressed as a series of inclined circular cross sections. The contact position of the roller and the workpiece is calculated from the inclination angle, center coordinates, and diameter of the cross sections, considering the geometrical shape of the roller. The blank shape and the target shape are interpolated along normalized tool paths to generate the numerical control command of the roller. By this method, we experimentally formed aluminum tubes into curved shapes with various radii of curvature, and the forming accuracy, thickness distribution, and strain distribution are examined. We verified that the curved shapes with the target radii of curvature can be accurately realized.

中文翻译：

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同步多道旋压形成的斜/弯曲管颈

在本文中，我们提出了一种通过同步多遍旋压将管成形为倾斜/弯曲形状的方法，其中，成形辊与主轴的旋转角度同步地沿径向往复运动，同时辊沿轴向往复运动。工件沿轴向方向逐渐将空管变形为目标形状。目标倾斜/弯曲形状表示为一系列倾斜的圆形横截面。考虑到辊的几何形状，从倾斜角，中心坐标和横截面直径计算辊与工件的接触位置。毛坯形状和目标形状沿着标准化的刀具路径插补，以生成辊的数控命令。通过这种方法，我们通过实验将铝管成型为具有各种曲率半径的弯曲形状，并检查了成型精度，厚度分布和应变分布。我们证实可以精确地实现具有目标曲率半径的弯曲形状。