6309 Bearing
45×100×25 mm
Specifications
Bore (d)
45 mm
OD (D)
100 mm
Width (B)
25 mm
Fillet radius
1.5 mm
Dynamic C
52.7 kN
Static C₀
30 kN
Fatigue limit Pᵤ
1.27 kN
Speed (grease)
7,000 rpm
Speed (oil)
9,000 rpm
Weight (open)
0.93 kg
Standard
ISO 15:2017
DIN
DIN 625
Variants (SKF suffix convention)
| Variant | SKF model | Weight (kg) | Description |
|---|---|---|---|
| Open | 6309 | 0.93 | No seals — for clean environments, re-greaseable |
| Rubber sealed (both) | 6309 2RS1 | 0.965 | Maintenance-free, best dust/moisture protection |
| Metal shielded (both) | 6309 Z | 0.945 | Lower torque than 2RS, good dust protection |
Brand Interchange
All brands below manufacture the 6309 to ISO 15:2017 — fully interchangeable on bore, OD, and width.
| Brand | Open | 2RS sealed | ZZ shielded |
|---|---|---|---|
| SKF | 6309 | 6309 2RS1 | 6309 Z |
| FAG | 6309 | 6309 2RS | 6309 Z |
| NSK | 6309 | 6309 2RS | 6309 ZZ |
| NTN | 6309 | 6309 2RS | 6309 ZZ |
| KOYO | 6309 | 6309 2RS | 6309 ZZ |
| NACHI | 6309 | 6309 2NSE9 | 6309 ZZE |
| Timken | 6309 | 6309 2RS | 6309 ZZ |
Chinese Manufacturer Alternatives
Dimensionally interchangeable with SKF/NSK per ISO 15:2017. Indicative FOB price: $3–$7 USD (MOQ 100 pcs, P0 open).
| Manufacturer | Model | Grade | Tier |
|---|---|---|---|
| ZWZ | 6309 | P0 | Mid-range |
| LYC | 6309 | P0 | Mid-range |
| C&U | 6309 | P0 | Budget |
| HRB | 6309 | P0 | Budget |
Old Chinese GB numbers: 309, 80309
Request Quote from Chinese FactoriesRecommended Fit
Normal load: k6 · Heavy: m6
Stationary: H7 · Rotating: M7
Frequently Asked Questions — 6309 Bearing
What are the dimensions of the 6309 bearing?
The 6309 bearing measures 45mm bore × 100mm outer diameter × 25mm width, with a fillet radius of 1.5mm. This conforms to ISO 15:2017.
What is the load rating of the 6309?
The 6309 has a dynamic load rating (C) of 52.7 kN and a static load rating (C₀) of 30 kN. These values are used in ISO 281 L10 life calculations.
What speed can the 6309 run at?
With grease lubrication, the 6309 has a reference speed of 7,000 rpm. With oil lubrication, the limit is 9,000 rpm.
Are SKF, NSK, FAG, and Timken 6309 interchangeable?
Yes. All major bearing brands (SKF, FAG, NSK, NTN, KOYO, NACHI, Timken) produce the 6309 to ISO 15:2017 dimensional standards. They are fully interchangeable on bore, OD, and width dimensions.
What Chinese brands make a 6309 equivalent?
ZWZ, LYC (Luoyang), C&U (Changzhou), and HRB (Harbin) all manufacture 6309 equivalents to ISO 15:2017. Old Chinese GB numbers: 309, 80309. All are dimensionally interchangeable with SKF/NSK.
What is the difference between 6309 open, 6309 2RS, and 6309 ZZ?
Open: no seals, suitable for clean environments with re-lubrication access. 2RS (rubber sealed both sides): maintenance-free, best for dusty or wet environments. ZZ (metal shielded): lower torque than 2RS, good dust protection but not waterproof. For most applications, 2RS is recommended.
What shaft tolerance fits the 6309 bearing?
For a rotating inner ring (most common), use shaft tolerance k6 for normal loads or m6 for heavy loads. For a non-rotating shaft, h6 or js6 is appropriate. Housing bore should be H7 for a stationary outer ring. Use our Bearing Fit Calculator for exact tolerance values.
How do I calculate 6309 bearing life?
L10 = (C/P)³ where C = 52.7 kN (dynamic rating) and P is your applied equivalent load (kN). L10h = L10 × 10⁶ / (60 × n), where n is speed in RPM. Use our Bearing Life Calculator to compute this automatically.