With great thickness transition of inner layer from major axis to minor axis, the inner cavity of
shrink-fitting flat container
would deform unevenly beyond the prescriptive dimension precision, which would put re-sinking of die into trouble. Thus, structure development of the
flat container was put forward. Considering geometric similarity, an idea of using elliptic inner layer structure was presented instead of circular shape. The numerical simulations of two-layer flat containers with two kinds of structures respectively subjected to the shrink fitting were made by ANSYS finite element analytical software. The deformation law and displacement of inner cavity were analyzed. Then corresponding actual experiments were carried out to testify them. Finally, the results indicated that displacement on the straight edge of inner cavity using elliptic structure is smaller than that using circular structure. Moreover, the deformation distribution of the former is more even than that of the latter on the whole cavity die. All these gave convenience to re-sinking of die and improved the manufacturing accuracy of parts.