Timken MM45BS100DUH Ball Screw Support Bearing Set

The Timken Fafnir MM45BS100 DUH is a matched duplex angular contact ball screw support bearing set engineered for high axial stiffness and precise shaft positioning in ball screw systems. It consists of two factory-matched single-row precision angular contact bearings with heavy preload (DUH), designed to carry combined radial and axial loads. Key dimensions include a 45 mm bore, 100 mm outside diameter, and a total set width of 45.0 mm (22.5 mm per bearing). The bearings use a phenolic outer land riding cage and are made from bearing steel with steel balls. Dynamic rating 16,010 lbf (71,200 N); static rating 21,000 lbf (93,400 N); contact angle 60°. This duplex set is intended to be factory-matched and not mixed with unmatched bearings. Common applications include CNC machining centers, ball screw assemblies, industrial automation equipment, precision positioning systems, and power transmission systems where high rigidity and accurate axial positioning are required. Common replacements include the Timken Fafnir MM45BS100 DUH matched set and the MM45BS100 DUL (light preload).