RHP7226TDUMP4Matched Pair Super-Precision Angular Contact Ball Bearings – 130 mm ID, 230 mm OD, 40 mm Width Each, Open, Phenolic Cage, Medium Preload, EP7, 2 Pcs

Product Description

What this part is

RHP 7226TDUMP4 super-precision angular contact ball bearings, matched pair, single row each, open. Bore: 130 mm. Outside diameter: 230 mm. Width: 40 mm per bearing. Precision: EP7, equivalent to ABEC 7 and ISO Class 4. Series: 72, light section.

Decoding the designation

7226: 130 mm bore in the ISO 72 dimension series. 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-7226-TA-DUM-EP7, where TA is the same phenolic cage and EP7 the same class, and the Fafnir form MM9126 WI CR DUM, where CR is a phenolic outer-land-riding cage.

What these specs mean in practice

EP7 is the ABEC 7 class: bore, outside-diameter, width and runout are held to super-precision tolerances, which is what makes a matched pair hold its preload predictably. Medium preload sits between light and heavy on the stiffness ladder, giving more axial rigidity and better position control than light preload at the cost of more running torque and heat. The outer-ring-guided machined phenolic cage runs to 120 °C and suits both grease and oil-air lubrication; its low mass and low friction coefficient are what make it standard on high-speed spindle bearings.

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: 80 mm.

Fitting notes

Straight bore, open on both faces, so lubrication and sealing come from the spindle design. Interference on the inner ring and a located outer ring are the normal arrangement for a preloaded pair.

Interchange guidance

Same envelope, 130 x 230 x 40 mm, in other schemes: SKF 7226 CD/P4A and FAG B7226-C-T-P4S-DUM, both 15° executions, and Fafnir MM9126WI CR DUM. Written forms in circulation: 7226TDUMP4, 7226 T DUM P4, 7226-T-DUM-P4, B-7226-TA-DUM-EP7, B7226TP4SDUM.