Step 4 of the forging process: Flow-forming the barrel. The name can be confusing, as it’s also used to describe cast wheels that go through this process as an extra step. The flow-forming process can be used on both cast and forged wheels to shape the barrel. In this step, the thick, unformed barrel portion of a forged wheel blank is drawn down over a drum under intense pressure, which stretches it out to its final width and profile. This step creates a dense barrel with the metal’s grain struc