RHP7932ETDUMP4Matched Pair Super-Precision Angular Contact Ball Bearings – 160 mm ID, 220 mm OD, 28 mm Width Each, Open, 25° Contact Angle, Phenolic Cage, Medium Preload, 2 Pcs

Product Description

What this part is

RHP 7932ETDUMP4 super-precision angular contact ball bearings, matched pair, single row each, open. Bore: 160 mm. Outside diameter: 220 mm. Width: 28 mm per bearing. Contact angle: 25°. Precision: EP7, equivalent to ABEC 7 and ISO Class 4. Series: 719, extra-light section, also written 71932.

Decoding the designation

7932: 160 mm bore in the extra-light section, catalogued as 71932. E: 25° contact angle. T: machined laminated phenolic cage, outer-ring guided, rated to 120 °C. DUM: duplex universally ground pair at medium preload. P4: EP7 precision, ABEC 7. The carton also carries the RHP B-series form B-7932-X3-TA-DUM-EP7, where X3 is the same 25° angle and TA the same phenolic cage, and the Fafnir form 3MM9332WI-DUM, where 3MM is again 25°.

Published ratings

Basic dynamic load rating Cr: 126 kN. Basic static load rating C0r: 125 kN. Permissible axial load Pa: 93.5 kN. Limiting speed: 4,800 rpm on grease, 7,400 rpm on oil or oil-air. Effective load centre a: 58.3 mm. Medium preload: 3,252 N, giving 592 N/µm axial rigidity across the pair. Mass: 3.12 kg (6.88 lb) per bearing. Recommended grease charge: 16 g per bearing.

What these specs mean in practice

The extra-light 719 section puts a 220 mm outside diameter on a 160 mm shaft, which is what makes it the standard choice for large machine-tool spindles where housing space is tight and stiffness per unit of mass matters. A 25° contact angle carries far more thrust than a 15° bearing on the same envelope. Medium preload delivers 592 N/µm of axial stiffness across the pair, roughly 40 per cent more than light preload on this size, at the cost of higher running torque and heat. The outer-ring-guided machined phenolic cage takes 120 °C and supports the 7,400 rpm oil-air figure against 4,800 rpm on grease.

Quantity and configuration

Two pieces, supplied as the DUM matched pair. Universally ground, so they mount back-to-back, face-to-face or in tandem and reach medium preload on assembly without shims. Stacked width across the pair: 56 mm.

Fitting notes

Shaft abutment diameter da: 170 mm minimum. Housing abutment diameters Da: 210 mm maximum, Db: 214 mm maximum. Fillet radii: ra 2 mm maximum, rb 1 mm maximum. Chamfer dimensions r 2 mm minimum, r1 1 mm minimum.

Interchange guidance

NSK 7932A5TRDUMP4 is the same bearing in NSK’s current scheme, since NSK owns RHP: A5 is the 25° angle, TR the outer-ring-guided phenolic cage. Also same spec: SKF 71932 ACD/P4A, FAG B71932E.T.P4S, Fafnir 3MM9332WI. Related size at a different angle, not a substitute: 71932 CD and RHP 7932X2, both 15°.