Model-based optimization of blade geometry in rolling-cut shearing to minimize common defects of the sheared edge

摘要

Rolling-cut shearing is commonly used for side trimming of heavy steel plates. The standard shape for the upper blade is circular. However, this standard shape may cause variations of the lateral process force and thus an unintended lateral displacement of the upper blade. The results are quality defects of the sheared edges. These defects are unevenness in longitudinal direction with peak-to-peak values of more than 2 mm, extended fracture zones, and excessive burr near the beginning and end of the periodic cut (cut-transition point). So far, there is a lack of investigations and countermeasures for these quality defects. Therefore, the current paper aims at avoiding or significantly reducing these common edge defects just by optimizing the shape of the upper blade of rolling-cut shears. The optimized shape should ensure straight and even edges. The feasibility of this idea was analyzed on an industrial rolling-cut trimming shear of AG der Dillinger Huttenwerke, Dillingen, Germany, by comparing cuts from its nominal blade with cuts from the optimized blade. In these experiments, the peak-to-peak values of the unevenness was reduced by more than 80%. The proposed optimization of the blade geometry is easily transferable to other rolling-cut trimming shears.