Statistical Analysis and Optimisation of Data for the Design and Evaluation of the Shear Spinning Process

This work proposes a research method that is a scheme that can be universally applied in problems based on the selection of optimal parameters for metal forming processes. For this purpose, statistical data optimisation methods were used. The research was based on the analysis of the shear spinning tests performed in industrial conditions. The process of shear spinning was conducted on the components made of Inconel 625 nickel superalloy. It was necessary to select the appropriate experimental plan, which, by minimising the number of trials, allowed one to draw conclusions on the influence of process parameters on the final quality of the product and was the starting point for their optimisation. The orthogonal design is the only design for three factors at two levels, providing non-trivial and statistically significant information on the main effects and interactions for the four samples. The samples were analysed for shape and dimensions using an Atos Core 200 3D scanner. Three-dimensional scanning data allowed the influence of the technological parameters of the process on quality indicators, and thus on the subsequent optimisation of the process, to be determined. The methods used proved to be effective in the design, evaluation and verification of the process.

Forming Mechanism of Asymmetric Cylinder With Oblique–Straight Flange Spinning

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.