SKF33015Metric Tapered Roller Bearing, Complete Cone and Cup, 75 x 115 x 31 mm, Steep-Angle 330 Series

Product Description

What this part is

An SKF 33015 single-row metric tapered roller bearing, supplied complete as a cone and its matching cup. Bore 75 mm, outside diameter 115 mm, overall width 31 mm. The tapered rollers run between a coned inner raceway and a coned outer raceway whose apexes meet on the bearing axis, which is the geometry that lets the bearing carry heavy radial load and heavy thrust in one direction at the same time.

Decoding the designation

The 330 series is the steep-contact-angle metric tapered roller series, and the trailing 15 is the bore code, giving 75 mm. The steeper raceway angle of the 330 series raises the proportion of the load the bearing takes axially compared with a shallower 302 or 320 series bearing on the same bore, and it does so within a comparatively wide section. No suffix follows the base number, so the bearing is the standard cage, standard tolerance and standard clearance form.

What these specs mean in practice

Contact angle governs the split between radial and axial capacity in a tapered roller bearing. A steep-angle 330-series bearing carries much more thrust for its size than a shallow-angle equivalent, and it is what a designer reaches for on a shaft where thrust dominates — a worm wheel, a bevel pinion, a vertical spindle. The penalty is that a given radial load induces a larger internal axial force, so the opposing bearing has to be sized for it. Because the cone and cup separate, the bearing has no internal clearance of its own: the running condition, from endplay through to preload, is set at assembly against the opposed bearing.

Quantity and configuration

1 set. Cone and cup supplied together, matched as a pair. Straight bore.

Fitting notes

The cone is an interference fit on the shaft seat and the cup a fit in the housing bore, so mounting force goes through the ring being fitted alone. Endplay or preload across the opposed pair is set after both rings are seated, and the setting is what determines both the bearing life and the shaft stiffness in service.

Interchange guidance

Same-envelope, same-series equivalents are FAG 33015, NSK HR33015J, NTN 33015U and Koyo 33015JR, all 75 x 115 x 31 mm single-row steep-angle metric tapered roller bearings supplied complete. A 32015 or 30215 shares the 75 mm bore but uses a shallower contact angle and a different envelope, so those are related sizes rather than substitutions. The cone and cup halves of a 33015 are matched to each other and are not published as separate part numbers in the metric scheme.