Tapered roller bearing
30308 Bearing Dimensions
30308 tapered roller bearing: bore 40 mm, dimensions 40x90x25.25 mm (ISO 355). Cone and cup widths, designation breakdown and size-equivalent codes.
30308 specifications
| Bore d | 40 mm |
|---|---|
| Outside diameter D | 90 mm |
| Total width T | 25.25 mm — assembled width of cup and cone |
| Seal / shield options | Open (cup and cone, no seals) |
| Material | GCr15 chrome bearing steel (rings and rolling elements) |
| Precision | P0 (standard); P6 on request |
| Radial clearance | Set during mounting (adjustable, not a C-class value) |
| Load ratings | Load ratings available on request for the specific batch and manufacturer. |
How to read the 30308 designation
| Segment | Meaning |
|---|---|
| 3 | Single row tapered roller bearing (metric, ISO 355) |
| 03 | Dimension series 03 |
| 08 | Bore code 08 → 40 mm bore. ISO bore code (00–03 = 10/12/15/17 mm; 04 and above = code × 5 mm). |
30308 interchange by brand
30308 is an ISO designation. The boundary dimensions are identical across manufacturers; only suffixes (seals, clearance, cage) differ.
| SKF | NSK | NTN | FAG | Timken | Note |
|---|---|---|---|---|---|
| 30308 | 30308 | 30308 | 30308 | 30308 | Same ISO designation |
Typical applications
- Vehicle wheel hubs and axles
- Gearboxes and reducers
- Agricultural machinery
- Conveyor pulleys
FAQ
Is 30308 the same size across brands?
Yes. 30308 is an ISO designation, so the bore, outside diameter and width are the same whichever manufacturer made it. Brand-specific suffixes only change details such as seals, clearance or cage.
Where are the load ratings for 30308?
Dynamic and static load ratings differ by manufacturer and batch, so they are not published on this page. Load ratings available on request for the specific batch and manufacturer.