Okuma PREX motors are compact, high-power, high-torque built-in motor/spindle units designed to eliminate belts and gears, which reduces vibration and bending sources to support stable, chatter-resistant machining across a wide operating range.
In turning applications, PREX-driven spindles are paired with large-bore bearing and spindle designs (for example, a bearing ID around 120 mm with an 80 mm spindle through-hole) and are shown with full-power performance up to 5,000 min⁻¹ with continuous ratings such as 15 kW and 281 N·m, plus higher short-duty power/torque capability for heavy cutting. For multitasking milling, the PREX motor is also used as the milling tool spindle in a radial turret configuration, with published figures such as 6,000 min⁻¹, 4.1 kW continuous (7.1 kW short duty), and 23.4 N·m continuous (40.4 N·m short duty) to support high material removal rates. Overall, the PREX series is presented as a spindle/milling-drive platform that combines high rigidity, wide-range constant power behavior, and fast axis/spindle dynamics to improve productivity without relying on mechanical transmission elements.
