铝合金管三滚轮推弯成形半径理论计算公式的验证

Verification of a theoretical calculation formula for aluminum alloy tube forming radius by three-roll-push-bending

对不同牌号和规格铝合金管材的三滚轮推弯加工进行了弯管半径的理论计算和实际测量。根据设备加工的不同弯管半径,利用有关公式计算出回弹后三滚轮推弯加工管材理论弯管半径;利用三维激光扫描和Matlab图像处理方式测得弯管实际回弹后的成形半径。对理论值与实测结果进行对比分析表明:随着成形半径和管材壁厚增大,理论计算值与实测结果的误差增大。本研究采用的理论计算公式适用于塑性变形程度较大、弯曲半径小于110 mm、壁厚不大于0.4 mm的管材的三轮推弯加工,此时弯曲半径的计算误差小于8%。理论公式可用于指导薄壁铝合金管的小弯曲半径的三滚轮推弯加工。

The theoretical calculation and practical measurement of bending radii of three-roll-push-bending for different designations and specifications aluminum alloy tubes were carried out. According to the different bending radii of the equipment, the theoretical bending radius of the tube processed by three-roll-push-bending after springback was calculated by using relevant formulas. By means of 3 D laser scanning and Matlab image processing, the forming radius of the bent tube after the springback was measured. The comparison between the theoretical value and the measured result shows that the difference between the theoretical calculated value and the measured result increases with the increase of the forming radius and the wall thickness of the tube. The theoretical calculation formula adopted in this study is applicable to the three-roll-push-bending of the tube with a large plastic deformation degree, the bending radius less than 110 mm and the tube wall thickness not greater than 0.4 mm. In this case, the calculation tolerance of the bending radius is less than 8%. The theoretical formula can be used to guide the three-roll-push-bending of thin-wall aluminum alloy tube with small bending radius.