Effect of cutting conditions on press cutting of a square pipe

Abstract

In press cutting of a square pipe, effects of cutting parameters such as the top angle of the punch, wall thickness, side length and material of the pipe on the distortion of the cross-section and surface decline of the cut end to the axis are discussed. Cutting force is also measured and discussed. When cutting with the top angle 60°, the first indentation into the top corner makes the material apart. And the surface at the side corners are rough, while this does not occur for the other angles. In the case of 90°, the shearing force becomes largest in the latter half of the cutting process. For 180°, the distortion of the cross-section is the largest. The measured and observed results show that the better top angle may be 120°. Surface decline of the cut end, which expresses the perpendicularity to the axis, becomes larger, as the wall thickness is increased with the ratio of the tool clearance to the wall thickness unchanged. In estimating the cutting force, the model when calculating the shear force in sheet shearing with a shear-angled punch is used. The estimated formula is also available in cutting the square pipe.