Fafnir3MM9109WI DULAngular Contact Ball Bearing – Straight Bore, 45 mm ID, 75 mm OD, 16 mm Width, Open, 25° Contact Angle, Light Preload, Duplex Universal Pair.

Product Description

What this part is

Fafnir 3MM9109WI-CR-DUL super-precision angular contact ball bearing, 9100WI spindle range, 45 x 75 x 16 mm. Bore Diameter: 45 mm. Outside Diameter: 75 mm. Overall Width: 16 mm. Contact Angle: 25°. Precision Class: ABEC 7/9 / P4S. Dynamic Load Rating: 25,600 N. Static Load Rating: 18,300 N. Limiting Speed: 17,700 rpm grease; 32,200 rpm oil. Item Weight: 0.24 kg (0.53 lb). Preload: Light. Cage Material: Phenolic. Rolling Elements: Ball. Bore Type: Straight. Closure Type: Open. Bearing Material: Chrome steel. Number Of Rows: 2. Mounting Arrangement: Universal. Lubricant: grease or oil. Series: 9100WI. Base Number: 3MM9109WI. GTIN: 087796072404.

Decoding the designation

3MM — 25° contact angle.

MM — Fafnir super-precision execution, ISO Class P4S, equivalent to ABEC 7/9.

9109 — 9100 spindle series, 45 mm bore, ISO 7009 envelope.

WI — low shoulder on both rings.

CR — phenolic cage.

DUL — duplex set of two universally ground bearings at light preload.

What these specs mean in practice

Contact Angle: 25°. The steeper angle carries more thrust than a 15° execution on the same envelope and trades some top speed for axial stiffness.

Dynamic Load Rating: 25,600 N per bearing, rated over one million revolutions. Static Load Rating: 18,300 N.

Limiting Speed: 17,700 rpm grease; 32,200 rpm oil. Oil feed nearly doubles the ceiling because it carries heat out of the contact as well as lubricating it.

Preload: Light. Light preload gives the highest speed capability of the preload ladder and the lowest heat generation.

Cage Material: Phenolic. A machined phenolic cage is light, damps vibration and holds oil in its own structure.

Item Weight: 0.24 kg (0.53 lb) per bearing.

Mounting data

Bore Type: Straight. Shaft backing shoulder diameter: 51.3 mm. Housing backing shoulder diameter: 69.3 mm. Maximum housing fillet radius the bearing corners will clear: 1 mm.

Mounting Arrangement: Universal — universally ground faces allow the pair to be set back-to-back, face-to-face or in tandem. The set is preload-established rather than clearance-set.

Quantity and configuration

Unit Quantity: 2 Pcs. One duplex set of two universally ground bearings at light preload, supplied together as the sale unit.

Interchange guidance

Cross-Reference 1: Timken 7009E-T-P4S-DUL. Cross-Reference 2: FAG B7009-E-T-P4S-DUL. Cross-Reference 3: SKF 7009 ACD/P4A DGA. Cross-Reference 4: NSK 7009A5TRDULP4. Cross-Reference 5: IBC 7009-E-T-P4S-DUL.

Cross-Reference 6: 2MM9109WI-CR-DUL shares the 45 x 75 x 16 mm envelope at a 15° contact angle and is a related size rather than a direct interchange.

Searchable forms of the designation: 3MM9109WICRDUL, 3MM9109WI-CR-DUL, 3MM 9109 WI CR DUL, 3MM9109WIDUL, 7009-A, 7009A5, 7009ACD.