Three-Roll Planetary Rolling Mill Motion Analysis and Test Research

Abstract

Against defects of three-roll fixed axis rolling mill caused by rolled piece rotating in process of rolling, presented three-roll planetary rolling scheme, designed the planetary transmission system structure, expounded planetary mill rolling process, analyzed movement relationship between planet carrier, roll and rolled piece according to planetary gear train transmission principle. The rolls do planetary motion and spinning motion both, the former acts on the rolled piece to make it do clockwise rotation movement, the latter acts on the rolled piece to make it do anti-clockwise rotation. The actual movement of rolled piece is combination of the two motions. The theoretical analysis and calculation shows that in rolling process of planetary mill, the speeds of above two kinds of motions are very close, directions are opposite. Due to rolls are inclined compare to the rolled piece, as a result rolled piece does axial movement with a speed of vsinα, radial rotation speed is 0.0029 times of planet carrier rotational speed. Thanks to complexity of extrusion and friction between rolls and rolled piece, the actual speed of rolled piece is approximately zero. Prototype rolling test has verified correctness of theoretical analysis and calculation.