Fafnir2MM9110WIDUMSuper-Precision Angular Contact Ball Bearing Pair – 50 mm Bore, 80 mm OD, 16 mm Width, 15°, Medium Preload

Product Description

What this part is

Fafnir 2MM9110WICRDUM, a super-precision angular contact ball bearing supplied as a universally ground duplex pair. Bore Diameter: 50 mm. Outside Diameter: 80 mm. Overall Width: 16 mm per bearing. Total Width: 32 mm mounted as a pair. Contact Angle: 15°. Rolling Elements: Ball. Number Of Rows: 1 per bearing. Bore Type: Straight. Closure Type: Open. Cage Material: Phenolic. Precision Class: ABEC 7/9 / P4S. Preload: Medium. Series: 9100WI. Base Number: 2MM9110WI. GTIN: 087796072442.

Decoding the designation

2MM — Fafnir super-precision spindle range at a 15° contact angle, ground to ABEC 7/9 (P4S) tolerances.

9110 — the 9100 light dimension series, bore code 10, which maps to the ISO 7010 envelope: 50 mm bore, 80 mm outside diameter, 16 mm width.

WI — low shoulder on both rings.

CR — phenolic cage.

DUM — duplex pair, universally ground, medium preload. Either face can be brought together, so the pair mounts back-to-back, face-to-face or in tandem.

What these specs mean in practice

Dynamic Load Rating: 27,900 N per bearing. Static Load Rating: 20,800 N per bearing. Limiting Speed: 16,300 rpm grease; 32,600 rpm oil. Item Weight: 0.516 kg (1.14 lb) for the pair. Internal Clearance: N/A — a preloaded set is clamped to a defined stiffness rather than run to a clearance. Medium preload sits between the light and heavy grades: more spindle stiffness and better axial location than light, at some cost in running heat. A 15° contact angle favours speed and radial rigidity over thrust capacity.

Mounting data

Shaft Backing Shoulder Diameter: 56.1 mm. Housing Backing Shoulder Diameter: 74.2 mm. Maximum Housing Fillet Radius: 1 mm (0.039 in) — the largest housing corner radius the bearing corners will clear.

Quantity and configuration

Unit Quantity: 2 Pcs. One universally ground duplex pair. The 16 mm figure is the width of a single bearing; the pair occupies 32 mm of shaft length when clamped together.

Interchange guidance

Direct super-precision equivalents on the 7010 envelope at 15° with medium preload: FAG B7010-C-T-P4S-UL, SKF 7010 CD/P4ADGB, NSK 7010CTRDUMP4, NTN 7010UCG/GNP4, RHP 7010CTDUMP4 and Koyo 7010C P4 DUM. SNFA VEX 50 /NS 7CE1 shares the 15° angle and envelope. A standard-tolerance 7010-C shares the envelope and angle only. Searchable variants include 2MM9110WIDUM, 2MM-9110-WI-DUM, 2 MM 9110 WI CR DUM and 2MM9110WICRDUM.