Technology

Conventional Metal Spinning

Conventional spinning is a core metal spinning process used to produce precise, axisymmetric components with near-constant wall thickness.

Conventional Spinning

In conventional spinning, the wall thickness of the metal blank remains nearly constant, with the finished part closely matching the original blank thickness. A rotating sheet metal blank is formed over a rotating mandrel using a roller tool that applies localized pressure. The roller follows a predetermined path with multiple passes, incrementally shaping the metal until the interior surface matches the mandrel contour.

In multipass conventional spinning, the number and direction of roller passes control the final wall thickness. Forward passes slightly thin the material, while backward passes redistribute metal to maintain uniformity and reduce springback. Intermediate and finishing passes, called planishing, remove surface waviness and enhance finish and dimensional accuracy.

Forming Action

Metal spinning imparts continuous localized plastic deformation, providing advantages such as flexible processing, low forming loads, non-dedicated tooling, high material utilization, low production costs, and improved mechanical properties.

Process Classification

Metal spinning includes conventional spinning, shear spinning, and flow forming, distinguished primarily by wall thickness after forming. Spun parts can take various shapes including domes, cylinders, cones, and complex combinations. Finished diameters are smaller than the original blank, while wall thicknesses remain consistent. Conventional spinning is governed by tensile-compressive stresses, aligning it with bending and deep drawing processes. Additional classifications include mandrel vs. mandrel-free, inner vs. outer spinning, opposing rollers, cold vs. hot spinning, manual, and CNC spinning.