RHP7210CTDUHP4Super-Precision Angular Contact Ball Bearing Pair – Straight Bore, 50 mm ID, 90 mm OD, 20 mm Width Each, Open, 15° Contact Angle, Heavy Preload, Universal Duplex, ABEC 7

Product Description

What this part is

RHP 7210CTDUHP4 super-precision angular contact ball bearings supplied as a universally ground duplex pair. Bore 50 mm, outside diameter 90 mm, width 20 mm per bearing, 40 mm across the assembled set. Straight bore, open on both faces, single row of balls per bearing, machined phenolic cage riding on the outer ring land.

Decoding the designation

72 is the ISO medium angular contact dimension series and 10 is the bore code, giving a 50 mm bore. C denotes a 15° contact angle in the RHP scheme. T is a fabric-base laminate phenolic cage. DU marks universally ground duplex bearings and H sets heavy preload. P4 is ISO Class 4, equivalent to ABEC 7. The carton also carries 2MM210WICRDUH, B7210X2TADUHEP7 and the legacy number 210HDH, whose 2MM and X2 codes confirm the 15° angle, whose CR code confirms the outer-land phenolic cage, and whose EP7 confirms the ABEC 7 class.

What these specs mean in practice

A 15° contact angle favours speed and radial stiffness over thrust capacity, which suits a high-rpm grinding or milling spindle. Heavy preload takes stiffness and running accuracy to their maximum for this angle, holding the shaft position under interrupted cut, and pays for it in heat generation and a lower speed ceiling than a light or medium set. The phenolic cage offsets part of that penalty because it is light and self-lubricating.

Quantity and configuration

Two pieces, a universally ground duplex pair. Universal grinding lets the two units stack as a back-to-back, face-to-face or tandem set with the heavy preload built into the ground ring faces, so the pair takes thrust in both directions when mounted back-to-back or face-to-face.

Fitting notes

Ring faces are ground flat and square for direct abutment, so preload develops when the shaft nut and housing cap are drawn fully home. Both oil and grease lubrication are used on this class, with oil preferred at the top of the speed range.

Interchange guidance

The SKF 7210 CD/P4ADGC is the same 15° angle, class and heavy-preload pairing. The Fafnir 2MM210WI-DUH is the same specification under the WI numbering scheme. A light or medium preload version of the same number is a related size rather than a substitution, because the preload sets the stiffness and the speed limit.