Fafnir2MM9126WIDUHSuper-Precision Angular Contact Ball Bearing – 130 mm Bore, 200 mm OD, 33 mm Width, 15° Contact Angle, Open, Phenolic Machined Cage, Heavy Preload Duplex

Product Description

What this part is

Fafnir 2MM9126WI-DUH super-precision angular contact ball bearing, 130 mm bore, 200 mm outside diameter, 33 mm width per bearing. Single row, open on both faces, machined phenolic outer-land-riding cage. ISO base number 7026.

Decoding the designation

In the Fafnir WI super-precision scheme the leading 2MM sets a 15° contact angle, and the MM prefix carries P4S precision — ABEC 7 bore and outside diameter tolerances with ABEC 9 running accuracy. The leading 9 of 9126 places the bearing in the ISO 70 light dimension series. WI identifies the ground spindle-bearing execution, CR the phenolic outer-land-riding cage, and DUH a duplex arrangement at heavy preload.

What these specs mean in practice

A 15° contact angle favours speed and radial stiffness over thrust capacity; a 25° bearing of the same envelope carries more axial load and runs slower. The phenolic cage is light and self-lubricating, which suits high spindle speeds and grease or oil-mist lubrication. Heavy preload raises axial and radial stiffness and reduces running accuracy scatter, at the cost of higher operating temperature.

Quantity and configuration

One bearing. Universally ground faces allow assembly in duplex back-to-back, face-to-face or tandem sets with a matching bearing of the same designation.

Fitting notes

Straight bore, mounted on an interference fit to the spindle journal. Faces are ground for stack assembly, so bearings are installed with the marked faces oriented per the chosen duplex arrangement. Clean, filtered lubricant is standard practice for a phenolic-caged super-precision bearing.

Interchange guidance

Same-envelope 15° super-precision equivalents include the SKF 7026 CD/P4A, FAG B7026-C-T-P4S and NSK 7026CTYNSULP4. A 7026A5 or 7026-E variant of the same size is a 25° bearing and a related size rather than a substitution.