Precision Forming of the Straight Edge of Square Section by Die-Less Spinning

Abstract

Die-less spinning is a forming process to achieve cone shape parts. It is suitable for small batch production because of low costs and short development cycle. In order to increase the forming accuracy of the square section die-less spinning process, the roller path is designed and amended. Using a 5-axis CNC spinning machine, the square section cone is spun and its edge arc degree is calculated. Roller path amendment coefficient is proposed and deduced through the geometric relationship. Based on the experimental result in which the amendment coefficient is employed, the second amendment coefficient is deduced and used to perform another spinning experiment. By comparison of the section edge arc degrees of the workpiece obtained with and without using the amendment coefficients, it is found that the forming accuracy in experiments with the amendment is remarkably enhanced.

Modification of roller path for square cone by die-less asymmetric spinning

“…By using the modified roller path, the squareness of the product improves a lot and the average value of λ drops from 15.9% to 4.1%. In our previous study [16], the roller path is modified by measuring the geometry of the formed part. It took three trial experiments for λ value (10) 330 20 30 40 50 60 70 80 20 30 40 50 60 70 80 Roller Path 0 30 60 90 120 150 180 210 240 270 300 330 20 30 40 50 60 70 80 20 30 40 50 60 70 80 Roller Path Fig.…”

“…The edges of the cone are arc lines instead of the straight lines. Jia et al [16] proposed a method for the roller path amendment which improves the geometry accuracy. The amendment is based on measuring the geometry of the product.…”

Experimental study and FEM analysis of forward hot dieless spinning

“…A new discretization method was proposed by Han et al [19] to estimate the thickness distribution during dieless spinning. Jia et al [20,21] used dieless spinning to produce the square section cone and non-axisymmetric cone.…”