Forming Mechanism of Planetary Conical Rolling

This research deals with the development of a new process for tube ironing. The process of tube ironing is done without sliding friction which is the main cause for galling and breakage in conventional ironing. In this process a number of rollers rotate around the cone while revolving around their respective axis. The process Planetary Conical Rolling is termed PCR. This process has the following advantages: (1) rollers are supported by a shaft being free of lateral force, (2) the diameter of the shaft is almost the same as the inner diameter of the product, (3) high rigidity of the shaft results in high accuracy of products, (4) rollers inclination does not allow slide between roller and material in the radial direction. Experiments are conducted on two types of processes, i.e., forward and backward process, and two aluminum materials, i.e., A1050 and A5052 with different rotation, feed rate and so on. The results show this process can produce thickness reduction larger than 0.89 with mirror-finished outer surface.