When steel bars are formed from a forging or hot-rolling process, they generally have surface imperfections like microcracks or discontinuous “skins” that are formed during the cooling process. Metal oxide layers can also build up over time. These imperfections have to be removed before the blank can be formed into a sufficient raw material for further processing. The raw stock can be later machined into finished pieces such as axles, piston rods, or extrusion blanks for manufacturing plastic tube. In all of these cases, it’s important to have a completely smooth, defect-free continuous surface with precise dimensions. That’s where the bar peeling process comes into play. It produces the smooth surfaces and critical dimensions for downstream parts processing.
Peeling processes are suitable for use on all different types of steel. Peeling is more commonly used on various grades of stainless steel, carbon steel, and spring steel. However, they can also be used on tempered steel and high-alloy blends, among others. Each grade is going to pose a different set of challenges in the peeling process.