摘要
回弹是空间弯管成形的主要成形缺陷。为了预测和补偿空间弯管成形中的回弹,通过编写用户幅值子程序(UAMP),将有限元法应用于空间弯管的成形和回弹分析,提出了一种从仿真结果中提取管材中心线的方法。通过圆柱螺线形弯管成形的仿真计算,建立了管材回弹前后中心轴线曲率、挠率的关系。提出了一种基于求解曲线基本方程的空间弯管模具型面补偿方法,论述了曲线几何补偿的数学依据。通过对曲率和挠率(均为非常值)曲线进行补偿计算和成形仿真,对该方法进行了验证。结果表明该方法能够有效补偿回弹误差,保证弯管精度。
Springback is a key defect in spatial tube bending. To predict and compensate spring- back in spatial tube forming, finite element method （FEM） was used to analyze the special tube ben- ding process and its springback. User subroutine to specify amplitude （UAMP） was employed in es- tablishing the FEM model. A centerline extraction method was presented and used to deal with FEM data. Through simulation bending of cylindrical spiral tubes, a mathematical relationship of curvature and torsion before and after sprinback was acquired. Based on solving essential function of spatial curve, a compensation method for spatial tube bending mold was developed and mathematical princi- ple of geometrical compensation was discussed. Springback compensation using the method mentioned above and verification FEM simulation were carried out with a curve whose curvature and torsion were not constant. Simulation results show that the method can compensate springback effectively and en- sure the accuracy of spatial tube bending.
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2013年第23期3249-3254,共6页
China Mechanical Engineering
