6909 Bearing
Bore (d) 45 mm
Outside diameter (D) 68 mm
Width (B) 12 mm
Inches (bore × OD × width) 1.7717 × 2.6772 × 0.4724″
Deep-groove ball bearing, thin section (6900) series. Seal/shield suffixes (ZZ, 2RS, …) change the closures, never these dimensions — a 6909-ZZ and 6909-2RS are the same size.
What the number means
- 6 — deep-groove ball bearing
- 9 — dimension series (thin section (6900))
- 09 — bore code × 5 = 45 mm
Neighboring sizes (thin section (6900) series)
| Designation | Bore | OD | Width |
|---|---|---|---|
| 6907 | 35 mm | 55 mm | 10 mm |
| 6908 | 40 mm | 62 mm | 12 mm |
| 6909 | 45 mm | 68 mm | 12 mm |
| 6910 | 50 mm | 72 mm | 12 mm |
Same bore, other series
Fits the same 45 mm shaft with a different OD/width envelope and load capacity.
- 6809 — 45 × 58 × 7 mm (thin section (6800))
- 6009 — 45 × 75 × 16 mm (extra light (6000))
- 6209 — 45 × 85 × 19 mm (light (6200))
- 6309 — 45 × 100 × 25 mm (medium (6300))
Common suffixes on a 6909
| Suffix | Meaning |
|---|---|
| ZZ / 2Z | steel shields both sides (metal, non-contact) |
| Z | steel shield, one side |
| 2RS | contact rubber seals both sides (SKF 2RS1, NSK DDU, NTN LLU) |
| RS | contact rubber seal, one side |
| 2RZ | low-friction non-contact seals both sides (NSK VV, NTN LLB) |
| C3 | radial internal clearance greater than Normal (common in motors) |
| C2 | radial internal clearance smaller than Normal |
| NR | snap ring groove in the outer ring, with snap ring |
| P6 / P5 / P4 | ISO precision classes (≈ ABEC 3 / 5 / 7) |