Fafnir2MM9105WIDUMC1Angular Contact Bearing – 25 mm ID, 47 mm OD, 12 mm Width, Open, 15° contact angle, Medium preload.

Product Description

What this part is

Fafnir 2MM9105WI-DUM matched duplex pair of super-precision angular contact spindle ball bearings, built by The Timken Company. Series: 9100WI. Bore: 25 mm. Outside Diameter: 47 mm. Bearing Width: 12 mm per bearing. Total Width: 24 mm for the pair. Contact Angle: 15°. Precision Rating: ISO P4S (ABEC 7/9). Preload: Medium. Cage Type: CR – Phenolic Outer Land Riding Cage. Cage Material: Phenolic. Rolling Elements: steel balls. Bearing Material: high carbon chrome steel. Bore Type: Straight. Closure Type: Open. Rows per Set: Duplex. Design Units: Metric. Timken’s world part number for this set is 7005C-T-P4S-DUM.

Decoding the designation

The 2MM prefix gives a 15° contact angle and ISO P4S accuracy. 9105 in the 9100WI series is the ISO 7005 envelope. WI denotes a low shoulder on both rings. CR is the phenolic outer-land-riding cage. DU marks a duplex set, and the trailing M sets medium preload.

What these specs mean in practice

Dynamic Radial Load Rating (C1): 12,900 N (2,910 lbf) per bearing. C1 ISO Dynamic Radial Rating per row: 11,700 N (2,640 lbf). Static Radial Load Rating (C0): 7,400 N (1,660 lbf) per bearing. Limiting Speed – Grease: 30,900 rpm. Limiting Speed – Oil: 61,800 rpm. Lubricant: grease or oil. A 15° contact angle favours speed and radial stiffness over thrust capacity. Medium preload raises axial and radial rigidity above the light grade while keeping most of the speed.

Quantity and configuration

Unit Quantity: 2 Pcs. Arrangement / Configuration: Matched duplex pair. Total Width: 24 mm assembled. The two bearings are ground as a set and mount together at the published medium preload.

Mounting data

Max Shaft Fillet Radius: 0.6 mm (0.024 in). Outer Ring To Clear Radius: 0.6 mm (0.024 in). Shaft Backing Shoulder Diameter: 29.9 mm (1.180 in). Housing Backing Shoulder Diameter: 42.6 mm (1.680 in).

Interchange guidance

Cross-references: 7005C-T-P4S-DUM, SKF 7005 CDGB/P4A, FAG B7005-C-T-P4S-UL, NSK 7005CTYNDUMP4. Searchable forms of the designation: 2MM9105WIDUM, 2MM9105WI-DUM, 2MM 9105 WI CR DUM, 2MM9105WIDUMC1, 7005C.