6308 Bearing
40×90×23 mm
Specifications
Bore (d)
40 mm
OD (D)
90 mm
Width (B)
23 mm
Fillet radius
1.5 mm
Dynamic C
41 kN
Static C₀
22.4 kN
Fatigue limit Pᵤ
0.95 kN
Speed (grease)
8,000 rpm
Speed (oil)
10,000 rpm
Weight (open)
0.685 kg
Standard
ISO 15:2017
DIN
DIN 625
Variants (SKF suffix convention)
| Variant | SKF model | Weight (kg) | Description |
|---|---|---|---|
| Open | 6308 | 0.685 | No seals — for clean environments, re-greaseable |
| Rubber sealed (both) | 6308 2RS1 | 0.71 | Maintenance-free, best dust/moisture protection |
| Metal shielded (both) | 6308 Z | 0.695 | Lower torque than 2RS, good dust protection |
Brand Interchange
All brands below manufacture the 6308 to ISO 15:2017 — fully interchangeable on bore, OD, and width.
| Brand | Open | 2RS sealed | ZZ shielded |
|---|---|---|---|
| SKF | 6308 | 6308 2RS1 | 6308 Z |
| FAG | 6308 | 6308 2RS | 6308 Z |
| NSK | 6308 | 6308 2RS | 6308 ZZ |
| NTN | 6308 | 6308 2RS | 6308 ZZ |
| KOYO | 6308 | 6308 2RS | 6308 ZZ |
| NACHI | 6308 | 6308 2NSE9 | 6308 ZZE |
| Timken | 6308 | 6308 2RS | 6308 ZZ |
Chinese Manufacturer Alternatives
Dimensionally interchangeable with SKF/NSK per ISO 15:2017. Indicative FOB price: $2.5–$5.5 USD (MOQ 100 pcs, P0 open).
| Manufacturer | Model | Grade | Tier |
|---|---|---|---|
| ZWZ | 6308 | P0 | Mid-range |
| LYC | 6308 | P0 | Mid-range |
| C&U | 6308 | P0 | Budget |
| HRB | 6308 | P0 | Budget |
Old Chinese GB numbers: 308, 80308
Request Quote from Chinese FactoriesRecommended Fit
Normal load: k6 · Heavy: m6
Stationary: H7 · Rotating: M7
Frequently Asked Questions — 6308 Bearing
What are the dimensions of the 6308 bearing?
The 6308 bearing measures 40mm bore × 90mm outer diameter × 23mm width, with a fillet radius of 1.5mm. This conforms to ISO 15:2017.
What is the load rating of the 6308?
The 6308 has a dynamic load rating (C) of 41 kN and a static load rating (C₀) of 22.4 kN. These values are used in ISO 281 L10 life calculations.
What speed can the 6308 run at?
With grease lubrication, the 6308 has a reference speed of 8,000 rpm. With oil lubrication, the limit is 10,000 rpm.
Are SKF, NSK, FAG, and Timken 6308 interchangeable?
Yes. All major bearing brands (SKF, FAG, NSK, NTN, KOYO, NACHI, Timken) produce the 6308 to ISO 15:2017 dimensional standards. They are fully interchangeable on bore, OD, and width dimensions.
What Chinese brands make a 6308 equivalent?
ZWZ, LYC (Luoyang), C&U (Changzhou), and HRB (Harbin) all manufacture 6308 equivalents to ISO 15:2017. Old Chinese GB numbers: 308, 80308. All are dimensionally interchangeable with SKF/NSK.
What is the difference between 6308 open, 6308 2RS, and 6308 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 6308 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 6308 bearing life?
L10 = (C/P)³ where C = 41 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.