Product Description:

The MRS381F-2N-0230-NNNN is a rotor element manufactured by Bosch Rexroth Indramat for the MRS Synchronous IndraDyn H Motors series. As the rotating core of a synchronous spindle motor, it partners with a matching stator to translate electromagnetic torque into the high-speed mechanical motion needed in CNC machining centers and automated tool spindles. Accurate mass distribution and a tightly controlled magnetic path enable smooth acceleration, low runout, and repeatable velocity profiles during continuous industrial duty cycles.

The rotor body is machined with an internal diameter of 230 mm, a dimension that establishes the air gap and keeps the magnetic circuit concentric. A frame length of F establishes the axial stack height, which influences the moment of inertia and spindle power bandwidth. Shaft coupling relies on a step interference fit; the resulting radial pressure secures the rotor without keys or splines. The assembly has an IP00 protection rating, so it must operate inside a sealed spindle housing that prevents contact with exposed components. Thermal tolerance is supported by Class F insulation, which permits temperatures up to 155 °C before the insulating material begins to degrade.

Installation is restricted to ambient temperatures between 0–40 °C; temperatures outside this range can alter tolerances and disturb the rotor’s dynamic balance. The component is supplied in the standard design, without auxiliary cooling passages or special surface treatments. A precisely ground rotor bore matches the interference steps on Bosch Rexroth spindle shafts to maintain uniform clamping pressure around the circumference. As part of the IndraDyn H synchronous spindle group, the rotor is compatible with the high-resolution feedback devices and field-oriented control algorithms used by Rexroth inverter drives.