RHPSuper Precision Angular Contact Ball Bearing 25x52x15 mm, 30 Degree Contact Angle, Phenolic Cage, Duplex Universal Medium Preload

Product Description

What this part is

A super-precision angular contact ball bearing in the 72-series, 25 mm bore × 52 mm outside diameter × 15 mm width. The 72-series is the medium section of the angular contact range — a heavier ring cross-section than a 70-series bearing of the same bore, so more load capacity in exchange for a larger outside diameter.

Decoding the designation

7205 is the ISO 72-series angular contact envelope, 25 x 52 x 15 mm. A is a 30° contact angle: the older RHP angle codes map across as X2 = 15°, X3 = 25°, X4 = 30°, which is why the alternate designation 7205X4TADUMEP5 appears on these parts, with X4 and A agreeing on 30°. T is a machined laminated phenolic cage, outer-ring guided. DUM is duplex universal, medium preload, with ground faces that let the set be assembled back-to-back, face-to-face or tandem without shimming. P5 is ISO tolerance class 5, equivalent to ABEC 5.

What these specs mean in practice

30° is the steepest of the common spindle angles and the most thrust-biased. It gives the highest axial stiffness and the best resistance to axial deflection under heavy one-way thrust, which is why it turns up in drilling and boring spindles, worm and bevel gear supports, and ball screw thrust positions. The cost is speed and heat: a 30° bearing runs hotter at a given rpm than a 15° bearing of the same envelope, and its limiting speed is lower. Because the angle drives so much of the behaviour, matching it across the spindle stack matters more than matching the brand. Contact Angle: 30°. Cage Material: Laminated phenolic. Precision Class: P5 (ISO class 5 / ABEC 5). Mass: 0.28 lbs.

Quantity and configuration

DUM denotes a matched duplex pair, ground and marked as a set for back-to-back, face-to-face or tandem mounting.

Interchange guidance

Equivalent and carton designations for this part include 7205X4TADUMEP5, where TA denotes the one-piece outer-ring-centred machined phenolic cage and X4 confirms the 30° angle. A 3MM205WI CR DUM marking also circulates against this envelope; in the Fafnir/Timken scheme the 3MM prefix denotes 25°, not 30°, so that designation is retained as a search term only and is not an angular equivalent. RHP spindle bearings passed to NSK, which is the current source for new production.