InfoCenter / What is Whirling? / Page 2 of 4
Cutting procedure and generation of chips
Cutting is the result of the whirling ring rotating eccentrically at high speed about the slowly rotating workpiece. By means of numerical control, the advancement of the workpiece rotationally and the advancement of the tool head longitudinally correspond to the thread pitch required.
The cutting plane of the tool head is controlled over a vertical axis to correspond to the pitch angle of the thread. The eccentricity of the whirling ring determines the depth of cut. Right and left handed threads can be cut. In each case the tool ring rotates in the same sense as the workpiece, and the direction of travel yields the desired left or right hand thread. The chips produced by whirling are generated in comma shapes, see figure 2. The tools are mounted in the tool ring, and thus move uniformly relative to the workpiece. Although whirling is a process of discontinuous cutting, the smoothness of chip formation is such that even hard and brittle metals can be cut, either with tools of high carbide and nitride content, or with ceramic tools.