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Availability:
20 in stock
Fafnir 3MM9310WI-DUM super precision angular contact ball bearing set, 50 x 72 x 12 mm, 25° contact angle, medium preload universal duplex, ABEC 7 / P4.
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| MFR / Brand | Fafnir |
|---|---|
| MPN | 3MM9310WI-DUM |
| GTIN | 087796202313 |
| Model | 3MM 9310 WI CR DUM / 71910 E T DUM P4 / 7910ACD 7910A5 |
| Bearing Type | Super-Precision Angular Contact Ball Bearing, Open, both faces |
| ID | 50 mm |
| OD | 72 mm |
| Width | 12 mm per bearing |
| Series | Fafnir ultra-light 9300WI (maps to ISO 719 series) |
|---|---|
| Preload | Medium |
| Base Number | 71910 |
| Industry Terms | Spindle bearing; super precision bearing; machine tool bearing; ultra-light series; duplex pair; matched set |
| Bore Shaft Size | 50 mm (1.9685 in) |
| Mpn Variants | 3MM9310WI-DUM; 3MM9310WIDUM; 3MM 9310 WI CR DUM; 3MM-9310-WI-DUM; 3MM9310WI |
| Manufacturer Status | Fafnir super-precision line, now Timken |
| Precision Class | ABEC 7 / P4 |
| Rolling Elements | Ball |
| Item Weight | 0.136 kg (0.30 lb) per bearing |
| Cage Material | Phenolic |
| Number Of Rows | 1 per bearing (2 rows in the mounted set) |
| Bore Type | Straight |
| Snap Ring Included | No |
| Harmonization Code | 8482.10.50.28 |
| Contact Angle | 25° |
| Common Misspellings | Fafner 3MM9310WI-DUM; Faffnir 3MM9310WI; 3MM9301WI-DUM; 3MM9310W1-DUM; 3MM 9310 WL DUM |
| Cross Reference 1 | FAG 71910-E-T-P4S-DUM |
|---|---|
| Cross Reference 2 | SKF 71910 ACD/P4ADGB |
| Cross Reference 3 | NSK 7910A5TYNDUMP4 - polyamide cage |
| Cross Reference 4 | 2MM9310WI-DUM - 15 deg vs 25 deg |
| Cross Reference 5 | 3MM9310WI-DUL - light vs medium preload |
Fafnir 3MM9310WI-DUM is a matched universal duplex set of two super precision angular contact ball bearings (DUM, medium preload), single row each, open, with a machined phenolic cage. Each bearing: 50 mm bore, 72 mm outside diameter, 12 mm width; stacked width across the pair 24 mm. Fafnir ultra-light 9300WI series, ISO 71910 envelope, 25° contact angle. Unit Quantity: 2 Pcs.
3MM — Fafnir super precision series, 25° contact angle.
MM — P4 precision class (ABEC 7).
9310 — Fafnir ultra-light 9300WI series, which maps to the ISO 719 family: 71910, 50 x 72 x 12 mm.
WI — low shoulder on both rings, the duplex form.
CR — phenolic cage.
DUM — universally ground duplex pair at medium preload.
Bore Diameter: 50 mm (1.9685 in). Outside Diameter: 72 mm (2.8346 in). Width: 12 mm (0.4724 in) per bearing. Total Width: 24 mm across the pair. Contact Angle: 25°. Precision Class: ABEC 7 / P4. Preload: Medium. Cage Material: Phenolic. Rolling Elements: Ball. Number Of Rows: 1 per bearing. Closure Type: Open. Bore Type: Straight. Item Weight: 0.136 kg (0.30 lb) per bearing. Maximum shaft or housing fillet radius: 0.6 mm (0.024 in). Unit Quantity: 2 Pcs. Harmonization Code: 8482.10.50.28.
The rings are ground as a matched unit, so the pair can be arranged back-to-back, face-to-face or in tandem and develops medium preload from the ground ring offset. Straight bore, open on both faces.
Same 71910 envelope at 25°: FAG 71910-E-T-P4S-DUM, SKF 71910 ACD/P4ADGB and NSK 7910A5TYNDUMP4 (polyamide cage). Related Fafnir sets: 2MM9310WI-DUM is 15°, 3MM9310WI-DUL is light preload. Carton forms: 71910 E T DUM P4, 7910ACD, 7910A5.
50 mm bore, 72 mm outside diameter and 12 mm width per bearing; the pair stacks to 24 mm.
25°. The 3MM prefix denotes 25°; the 2MM prefix is 15°.
DUM is a universally ground duplex pair at medium preload.
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