Selecting a four-roller rolling machine requires a deep dive into material thickness, yield strength, and bending diameter. Unlike three-roller machines, the four-roller design allows for pre-bending of both ends of the plate without flipping it, which significantly increases efficiency. You must prioritize machines with NC or CNC control systems for high-precision repetitive tasks. Ensure the rollers are made of high-quality forged alloy steel (such as 42CrMo) and have undergone induction hardening to prevent surface wear during heavy-duty operations.