中文摘要：

依据多次三点弯曲压力矫直控制策略，分别给出了基于最小二乘曲线拟合原理和基于弯曲变形能相等原理的最优载荷修正系数的确定方法．由有限元仿真结果可知，前者计算出的最优载荷修正系数偏大，这是由于忽略了当加载弯矩大于理论矫直弯矩时对管件的影响远大于加载弯矩未达到理论矫直弯矩时的影响，而包含该因素影响的基于弯曲变形能相等原理计算出的最优载荷系数则比较适用．不同几何尺寸、不同初始挠度分布、不同矫直次数的小尺寸管坯矫直的物理模拟实验结果验证了基于弯曲变形能相等原理计算最优载荷修正系数的可行性与可靠性，可将初始直线度为4‰～10‰的管件矫正到1．1‰以内．这为多次三点弯曲压力矫直控制策略提供了便捷途径，也为自动化和智能化矫直奠定了基础．

英文摘要：

To optimize load correction coefficient, based on press straightening control strategy with multi-step three-point bending process, two methods of least squares curve fitting and equivalent bending deformation energy were proposed. The simulation results of the Longitudinally Submerged Arc Welding（ LSAW） pipe show that the optimum load correction coefficient calculated by least squares curve fitting method is bigger than normal. This is due to that, when the actual loading moment is greater than the theoretical straightening moment, the impact on the pipes is greater. However, the optimum load correction coefficient calculated by the equivalent bending deformation energy method, is more applicable, which is verified by the straightening physical simulation experiments of small sized pipes with different geometries, initial deflection distribution and straightening step. The straightness of the pipes with their initial straightness of 4‰~10‰ can be improved within 1.1‰. Thus, this method provides a convenient way to carry out the press straightening control strategy with multi-step three-point bending process.