Forming Mechanism of Asymmetric Cylinder With Oblique–Straight Flange Spinning

Abstract

The asymmetric cylinder with oblique–straight flange spinning has the potential to become a production process for this shape of the aerospace part. This complex shaped part was attempted to be formed by synchronous multipass spinning from a blank disk of 6061-O aluminum alloy with 1.15-mm thickness. The working principle of synchronous multipass spinning focuses on the fact that the radial and axial positions of the roller are synchronized with the spindle rotation to form the roller path. The roller path was calculated by dispersing a pass set into numerous points. The dimensional space between two points from the corresponding curves in a single-pass set was integrated into the trajectory around the circumference. Here, a pass set is the path along which the roller propagates in the two-dimensional space defined by the radial and axial directions. This shape was confirmed to be spun, and the formation mechanism of this spinning process was investigated. Contrastive experiments with paired arcs and pairs of straight lines as roller paths were performed on a spinning machine. The working condition of the cylinder wall with pairs of straight lines roller path was broken because of the higher pull resistance from the remaining part of the flange. The working condition of the flange of the paired arcs follows the law of shear spinning approximately that the cylinder wall forming does not comply. Suitable metal distributions for the flange and an appropriate force state for the cylinder wall are realized by the paired arcs roller path in the spinning process to form the asymmetric cylinder with oblique–straight flange. This provides a theoretical basis for the spinning of the asymmetric cylinder with the oblique–straight flange.