Three-dimensional finite element analysis of effects of roller intervals on tool forces and wall thickness in stagger spinning of thin-walled tube

Abstract

Roller intervals are the key parameters of the stagger spinning process, which affect the shape accuracy and productivity of the products. In this article, the effects of different roller intervals in axial and radial directions on tool forces, wall thickness, and strain and stress variations in stagger spinning have been analyzed numerically by the finite element analysis. The results show that with the increasing of the axial roller intervals, the differences between tool force components (axial, radial, and tangential) become lower at first, and then have the trend to be higher. The similar phenomenon on tool force occurs when the radial interval of roller 3 increases and that of roller 2 decreases. Wall thickness variations are mainly affected by axial roller intervals; the bigger the axial intervals are, the higher the variations of wall thickness that would be seen. Meanwhile, the real reductions of wall thickness are mainly affected by radial roller intervals. When the radial interval of roller 3 is larger than that of roller 2, there would be a higher real wall thickness reduction.

A study of 3D finite element modeling method for stagger spinning of thin-walled tube

“…There have also been some reports on FE modeling methods in the case of stagger spinning (Xue et al, 1997;Tan, 2009;Zhang et al, 2009;Ge, 2012;Li et al, 2013). In these simulations, some parameter setting conditions and simplified approaches of FE modeling were proposed to improve the computational efficiency.…”

“…Displacement boundary. During the process of simulation, the roller system was fed in the displacement boundary as the blank and mandrel were fixed (Tan, 2009;Zhang et al, 2009;Li et al, 2013). It is inconsistent with the actual production condition.…”

“…Single-precision mode. Default singleprecision calculation was applied, and the influence of truncation error was not given enough attention (Li et al, 2013).…”

“…Time truncation. Artificially shortened termination time was used to break off the simulation for time-history result extraction as the long simulation time for the stagger spinning process (Li et al, 2013).…”

“…Interference phenomenon. Because of the lack of effective means of prevention, interference phenomenon occurred frequently in the setting trials (Ge, 2012;Li et al, 2013) to investigate the influence of parameters, such as intervals, which had significant influence on the accuracy and stability of the results.…”