SKF 21309K Spherical Roller Bearing

SKF 21309K is a double-row spherical roller bearing with a tapered bore, sized 45 × 100 × 25 mm. The bearing combines two rows of barrel-shaped rollers with an inner race and outer race that share a spherical contact surface, delivering high radial load capacity while tolerating a degree of shaft misalignment common in rotating machinery. The K suffix indicates a taper-bore variant, enabling mounting on a matched tapered shaft and offering installation flexibility in compact, high-load assemblies. The 45 mm bore, 100 mm outer diameter, and 25 mm width establish its footprint and mating clearances within SKF’s spherical roller bearing family. This model is designed for demanding applications where reliable radial support is required under heavy loads, and where precise shaft alignment cannot always be guaranteed. When selecting mounting arrangements, engineers typically follow OEM specifications and SKF guidelines for taper-bore bearings to ensure proper clamping, preload, and service life. The 21309K is compatible with SKF’s range of standard accessories and fittings used with taper-bore spherical bearings, supporting straightforward field replacement in maintenance programs.