薄壁不锈钢管数控绕弯成形数值仿真及工艺研究

针对航天某型号薄壁弯管成形难度大、尺寸精度低等问题,提出了数控绕弯成形替代拼焊成形,分析数控绕弯工艺特点及参数确定方法。建立模型对成形工艺参数进行有限元仿真,分析弯曲速度及芯头直径缩减量对不锈钢管成形影响,并通过试验得到优化的工艺参数。结果表明弯曲速度为8mm/s、减小芯头缩减量为0.6mm时,成形零件截面畸变不超过4%,最小壁厚0.65mm,弯曲后管材产生形变强化效果,组织更为细密,成行排列的方向性更明显,提高了零件强度。

Numerical Simulation and Technological Research of Numerical Control Bending in Thin-Walled Stainless Steel Tube

To deal with the difficulty of forming certain aerospace type thin-walled elbow with low dimensional accuracy, this paper puts forward a new method of numerical control bending forming instead of tailor-welded forming, and analyses the characteristics of numerical control bending and the rule of technological parameters. Finite element simulation model is established to analyze the influence of bending speed and core diameter reduction on forming and optimized parameters are obtained by experiments. The result shows that under the the process parameter of bending speed 8mm/s and core diameter reduction 0.6mm, the forming distortion rate does not exceed 4% with the minimum wall thickness of 0.65mm. Fiber tissue is compacted and the directionality of row arrangement is more obvious which formed the deformation strengthening effect to improve the strength of thin-walled elbow.