三旋轮错距旋压下超薄壁筒内径成形精度研究

Research on forming precision of inner diameter of ultra-thin wall tube in three roller stagger spinning

超薄壁筒形件在装配和服役过程中,对内径精度有较高的要求。利用Msc.Marc有限元分析软件,建立大径厚比超薄壁筒有限元模型。通过测量筒形件轴向不同位置处的内径值,得到内径偏差和内径波动沿轴线的分布规律,由此得到不同的工艺参数（旋轮圆角半径、进给比、旋轮轴向间距和径向间距）对内径成形精度的影响。结果表明：随着圆角半径的减小,内径偏差及内径波动值均降低,采用修正旋轮圆角半径时内径精度最好;进给比越小,内径偏差越大,则内径波动越小,综合考虑后取进给比f=1.0 mm·r^-1;随着旋轮轴向间距的增大,内径偏差及内径波动均呈现先减小后增大的规律,旋轮轴向最优间距C=1.5 mm;而旋轮径向间距按照等旋压力分配时内径精度最好。旋压实验表明,采用优化后的工艺参数能获得满足内径精度要求的产品。

The ultra-thin wall tube has a high requirement for the accuracy of the inner diameter in the process of assembly and service.A finite element model of ultra-thin wall tube was established by finite element analysis software Msc. Marc,and the distributions of inner diameter deviation and inner diameter fluctuation along the axis were obtained by measuring the inner diameter of the tube at different axial positions. Thus,the influences of different process parameters（ roller radius,feed ratio,roller radial distance and roller axial distance）on the inner diameter forming precision were obtained. The results show that the inner diameter deviation and the inner diameter fluctuation decrease with the decrease of roller radius,and the precision of the inner diameter is the best when the updated roller radius is used.Furthermore,the smaller the feed ratio is,the larger the inner diameter deviation is,but the inner diameter fluctuation is on the contrary,and the optimal value of feed ratio f is 1 mm·r^-1. With the increase of roller axial distance,the inner diameter deviation and the inner diameter fluctuation decrease first and the increase,and the optimal value of roller axial distance C is 1. 5 mm. In the end,when roller radial distance of spinning rollers is arranged according to the principle of equal spin pressure,the inner diameter precision is the best. The spinning test shows that the spinning product can meet the requirements of the inner diameter by the optimized process parameters.