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Timing Belt Pulleys and V-Belt Sheaves: Matching Belt Drive Components Correctly
Belt drives may appear simple, consisting of two wheels and a belt for power transfer.
Availability:
31 in stock
Super-precision angular contact ball bearing, 30 x 72 x 19 mm, straight bore, open, phenolic cage, ABEC 7 / P4, Fafnir 300WI spindle series.
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$189.07
31 in stock
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| MFR / Brand | Fafnir |
|---|---|
| MPN | MM306WI-2 |
| Model | MM 306 WI 2 CR |
| Bearing Type | Super-Precision Angular Contact Ball Bearing (spindle), Open, both faces |
| ID | 30 mm |
| OD | 72 mm |
| Width | 19 mm |
| Base Number | 306 |
|---|---|
| Industry Terms | spindle bearing; super precision bearing; machine tool bearing; 300WI series; phenolic cage bearing; angular contact spindle bearing |
| Common Misspellings | MM306W1-2; MM3O6WI-2; MM 306WI 2 |
| Bore Shaft Size | 30 mm |
| Mpn Variants | MM306WI-2; MM306WI2; MM-306-WI-2-CR; MM 306 WI 2 CR; MM306WI; MM306WICR |
| Manufacturer Status | Fafnir super-precision line, now Timken |
| Precision Class | ABEC 7 / P4 |
| Series | Fafnir 300WI spindle series (ISO 03 heavy dimension series) |
| Cage Material | Phenolic |
| Number Of Rows | 1 |
| Bore Type | Straight |
| Snap Ring Included | No |
| Harmonization Code | 8482.10.50.28 |
| Additional Attributes | Low shoulder on both rings (WI); single row; spindle-grade; usable in duplex sets |
| Application Types | machine tool spindles; grinding spindles; high-speed spindle assemblies; precision rotary tables |
| Cross Reference 1 | Fafnir 2MM306WI - 15 deg contact angle |
|---|---|
| Cross Reference 2 | Fafnir 3MM306WI - 25 deg contact angle |
Fafnir MM306WI-2 super-precision angular contact ball bearing, 30 mm bore, 72 mm outside diameter, 19 mm width. Single row, straight bore, open on both faces, phenolic cage, ABEC 7 / P4 precision. Timken catalogues the 300WI series as Fafnir spindle angular contact ball bearings alongside the 9100WI, 9300WI and 200WI families.
MM — Timken super-precision spindle prefix, P4 precision class (ABEC 7). A bare MM carries no contact angle; 2MM is 15° and 3MM is 25°.
306 — bore code 06 = 30 mm bore, 300 heavy dimension series (ISO 03).
WI — low shoulder on both rings, the form used for duplex sets.
CR — phenolic cage.
Bore Diameter: 30 mm. Outside Diameter: 72 mm. Overall Width: 19 mm. Bore Type: Straight. Rolling Elements: Ball. Number Of Rows: 1. Closure Type: Open. Cage Material: Phenolic. Precision Class: ABEC 7 / P4. Series: Fafnir 300WI spindle series (ISO 03 heavy dimension series).
Straight cylindrical bore for an interference-fit shaft seat, with the outer ring located in a bored housing. Single-row bearings of this type carry axial load in one direction and are mounted against a second bearing to locate the shaft both ways.
Related sizes in the same 30 x 72 x 19 mm envelope: Fafnir 2MM306WI (15° contact angle) and Fafnir 3MM306WI (25° contact angle). The contact angle changes how thrust and speed are balanced.
MM is the P4 class (ABEC 7) in Timken’s Machine Tool Catalog.
30 mm bore, 72 mm outside diameter and 19 mm width, single row with a straight bore.
A bare MM prefix carries no contact angle. The 2MM version is 15° and the 3MM version is 25°.
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Belt drives may appear simple, consisting of two wheels and a belt for power transfer.
Tapered, cylindrical, and spherical roller bearings all solve the same basic problem, carrying more load
If you pulled a bearing off general industrial equipment at random, there’s a good chance
Our team can locate, cross-reference, and source all parts.
Our team can locate, cross-reference, and source all parts.
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