SKF71906ACXP4ADGASuper-Precision Angular Contact Bearing – 30 mm ID, 47 mm OD, 9 mm Width, Open, 25° Contact Angle, Light Preload

Product Description

What this part is

SKF 71906-ACXGA/P4A super-precision angular contact ball bearing. Bore: 30 mm. Outside diameter: 47 mm. Width: 9 mm. Series: 719, extra-light, single row. Contact angle: 25°. Precision Class: P4A. Design: high-capacity D. Open on both faces, one-piece inner and outer rings, machined cage. Country of origin as recorded on this listing: Italy.

Decoding the designation

71906 = 719 extra-light series, 30 mm bore. AC = 25° contact angle. GA = universal matching at preload class A, light. P4A = SKF super-precision tolerance class. The 25° angle is confirmed three ways by the carton’s own cross-references: Fafnir 3MM9306WI, where 3MM is 25°; FAG B71906E, where E on a B719 designation is 25°; and NSK 7906A5, where A5 is 25°. Searchable forms: 71906-ACXGA/P4A, 71906ACXGA/P4A, 71906 ACX P4A DGA, 71906ACXP4ADGA, 7906, 7906A5.

What these specs mean in practice

A 25° contact angle carries more thrust than the 15° execution on the same envelope and runs at a lower speed ceiling. At this size the design carries 20 balls of 4.762 mm. Universal matching means the faces are ground so bearings from the range mount together back-to-back, face-to-face or in tandem without shims. Preload class A is the light setting, which favours speed and lower heat generation over maximum stiffness.

Load rating and mass

Basic dynamic load rating C: 6.76 kN (1,520 lbf). Mass: 0.049 kg (0.11 lb). Reference grease quantity: 0.63 cm³.

Quantity and configuration

One bearing ships. Axial load is carried in one direction, so a two-direction location uses a second bearing from the range set against it.

Fitting notes

Shaft abutment diameter da: 32 mm minimum. Housing abutment diameters Da 45 mm and Db 45.6 mm maximum. Fillet radii ra 0.3 mm and rb 0.2 mm maximum. Chamfer dimensions r1 0.3 mm and r2 0.2 mm minimum. Inner ring shoulder diameter 35.6 mm, outer ring shoulder diameter 41.4 mm. Oil nozzle position dn: 36.8 mm. As a preloaded universally matchable bearing it carries no running clearance, so the internal clearance field reads N/A.

Interchange guidance

Direct equivalents at the same 25° angle and light preload: Fafnir 3MM9306WI CR DUL, FAG B71906E.T.P4S.UL, NSK 7906A5TRSULP4. Related size: 71906 CDGA/P4A shares the 30 x 47 x 9 mm envelope at a 15° contact angle, with a basic dynamic rating of 7.15 kN and a static rating of 4.55 kN. It trades thrust capacity for speed and is a different part rather than a substitution.