Experimental Investigation on the Geometrical Accuracy of the CNC Multi-Pass Sheet Metal Spinning Process

Abstract

Abstract:The geometrical accuracy of multi-pass sheet metal spinning products is crucial in many applications. Aerospace, petroleum, and chemical industries motivated the development of modern spun components of complicated shapes with special functionality, but a substantial research lag exists behind this progress. Due to the localized plastic deformation involved, careful control of dimensions and form is required in spinning procedures. In this study, two sets of experiments were implemented for cup manufacturing using a retrofitted computer numerically controlled (CNC) spinning machine to identify the critical factors affecting product geometry and reveal their influence on the shape accuracy of the spun cups. The first set is a screening experiment to determine the most significant parameters and the second provides the optimum processing conditions affecting cup quality. The feed ratio, number of spin-forming passes, spinning ratio, and lubrication were found to have the most important effect on the geometry of the spun cups. Optimum quality with a higher processing speed (productivity) was achieved under a lubricated condition using a larger number of spin-forming passes at a high feed ratio, diminishing the commonly adopted rule of slow spinning for accurate products and reflecting a significance for state-of-the-art spinning practice. The findings of this paper introduce a basis for a spinning quality database.

Experimental estimation and numerical optimization of ‘cylindricity’ error in flow forming of H30 aluminium alloy tubes

“…All the three parameters were varied at 4 levels within a feasible range of flow forming without defects. According to the design of experiment (DOE) concept, a full factorial design comprising of 4 3 (i.e., 64) components has been considered. Consequently, three selected input parameters, i.e., feed speed ratio, axial stagger, and in-feed, were taken into consideration at 4 equal levels of variations.…”

“…The flow forming trials have been designed based on full factorial DOE having 3 factors, and 4 levels for each factor. Hence, a total number of 64(= 4 3 ) experiments have been carried out. The cylindricity value for each tube is measured as a response parameter after each forming operation.…”

“…Jiang et al [2] have proposed an accurate and efficient methodology to evaluate the cylindricity error. Alrazzaq et al [3] have carried out an experimental investigation on geometrical accuracy for the metal spinning process and established a relation between spinning Supplementary Information The online version contains supplementary material available at(https ://doi.org/10.1007/s4245 2-020-04074 -2) parameters and roundness. Analysis and validation of the phenomenon of diametrical growth with the change in input parameters have been attempted by Fong et al [4].…”

Effect of Intermediate Path on Post-Wrinkle Initiation of the Multi-Pass Metal Spinning Process: Analysis in the Rotating Reference Frame

“…According to Equation (15), there is an advantage when choosing the center of the roller so that it lies on the x-z plane where the y axis is zero. The explicit formula can be written in the matrix form.…”

“…Li et al [6], Abd-Alrazzaq et al [15], and Xia et al [16] studied the influential parameters of the spinning process via experiments using a computer numerical control (CNC) machine. They first presented the most significant parameters and then explained how they optimized those parameters for the minimum radial spinning force and tangential spinning force, which are considered to represent maximum spinning efficiency.…”