Tube-Rolling
Schematic illustration of various tube-rolling processes: (a) with fixed mandrel; (b) with moving mandrel; (c) without mandrel; and (d) pilger rolling over a mandrel and a pair of shaped rolls. Tube diameters and thicknesses can also be changed by other processes, such as drawing, extrusion, and spinning.
Shape Rolling
Ring Rolling – Thick ring small diameter transformed into thin ring, large diameter – Used in Jet Engines, large ring gears – Advantages • Circular shapes with no joins can be made with a variety of cross sections • short production runs, material savings, close tolerances, and favorable grain flow direction
Homeworks
What is the result of roll bending in flat rolling? How to prevent? In which situation the residual stress on the surfaces of the rolled products is compressive and tensile in the bulk? And in which situation the residual stresses are opposite to the previous case? Why?