Timken 2MM9318WI DUM Angular Contact Ball Bearing

Timken Fafnir 2MM9318WI DUM is a factory‑matched duplex set of super precision single‑row angular contact ball bearings designed for high‑speed machine tool spindles that demand exceptional rigidity, low runout, and precise shaft positioning. This duplex pair from the 9300WI series is factory matched with medium preload (DUM) and carries the Manufacturing Part Number 2MM9318WI DUM and World Part Number 71918C-T-P4S-DUM. It features a 90 mm bore, 125 mm outside diameter, and 18 mm per bearing width (36 mm for the duplex assembly), a 15° contact angle, and ISO P4S precision. The bearing uses a CR outer land riding cage with an MBR phenolic cage and provides static radial load ratings of 39,200 N and dynamic ratings of 40,900 N per bearing, with limiting speeds of 12,360 rpm grease or 24,720 rpm oil. Ideal for CNC machining centers, high‑speed milling machines, precision lathes, grinding machines, and machining spindles.