RHPSuper-Precision Angular Contact Ball Bearing – 45 mm ID, 85 mm OD, 19 mm Width, Open, 15° Contact Angle, Phenolic Cage, Light Preload

Product Description

What this part is

RHP 7209CTBSULP6 super-precision angular contact ball bearing, single row, open. Bore: 45 mm. Outside diameter: 85 mm. Width: 19 mm. Contact angle: 15°. Precision: EP3, corresponds to ABEC 3 and P6. Series: 72, light section.

Decoding the designation

7209: 45 mm bore in the ISO 72 dimension series. C: 15° contact angle. T: machined laminated phenolic cage, outer-ring guided, rated to 120 °C. SUL: single universally ground at light preload. P6: EP3 precision, ABEC 3. The carton also carries the RHP B-series form B7209X2TULEP3, where X2 is the same 15° angle, and the Fafnir form M209WI CR SUL.

Published ratings

Basic dynamic load rating Cr: 51.5 kN. Basic static load rating C0r: 28.8 kN. Permissible axial load Pa: 19.6 kN. Limiting speed: 17,700 rpm on grease, 27,000 rpm on oil or oil-air. Effective load centre a: 18.2 mm. Light preload: 254 N, giving 67 N/µm axial rigidity across a back-to-back or face-to-face pair. Mass: 0.406 kg (0.90 lb). Recommended grease charge: 2.5 g.

What these specs mean in practice

A 15° contact angle is the high-speed end of the angular contact range, trading thrust capacity for speed and radial stiffness against a 25° bearing on the same envelope. The outer-ring-guided machined phenolic cage takes 120 °C and its low mass is what supports the 27,000 rpm oil-air figure against 17,700 rpm on grease. Light preload delivers 67 N/µm of axial stiffness per pair with modest running torque. EP3 tightens bore, outside-diameter and runout tolerances over a standard-class bearing.

Quantity and configuration

1 Pc. Universally ground, so two or more mount back-to-back, face-to-face or in tandem and reach light preload on assembly without shims.

Fitting notes

Shaft abutment diameter da: 52 mm minimum. Housing abutment diameters Da: 78 mm maximum, Db: 80 mm maximum. Fillet radii: ra 1 mm maximum, rb 0.6 mm maximum. Chamfer dimensions r 1.1 mm minimum, r1 0.6 mm minimum.

Part number forms and nearby parts

NSK owns RHP and lists this size as 7209CTRSULP4 (C is the 15° angle, TR the outer-ring-guided phenolic cage, SUL the single universal light grind), at P4 accuracy rather than P6. Other makers at 15° and P4: SKF 7209 CD/P4A and FAG B7209-C-T-P4S. Fafnir M209WI CR SUL is the carton’s own cross. Related size at a different angle, not a substitute: 7209E and 7209X3, both 25°.