Bearing L10 Life Calculator
Expected hours before 10% of identical bearings fail
Bearing कितने घंटे चलेगी — load और rpm से calculate करें
Bearing L10 life is the statistical life — the number of operating hours that 90% of identical bearings under the same load will exceed before the first fatigue failure. The standard ISO 281 formula is L10h = (10⁶ / 60N) × (C/P)ᵖ, where C is the basic dynamic load rating from the bearing catalogue (in kN), P is the equivalent dynamic load on the bearing (kN), N is rotational speed (rpm), and p is 3 for ball bearings or 10/3 (≈3.33) for roller bearings. Example: an SKF 6205 deep-groove ball bearing has C = 14 kN; running at 1440 rpm with P = 2 kN load, L10h = (10⁶ / (60 × 1440)) × (14/2)³ = 11.57 × 343 = 3,970 hours. The same bearing at half the load (P = 1 kN) lasts 8× longer because the cube ratio amplifies the benefit. This calculator handles both ball and roller bearing types and flags when C/P < 2 (bearing severely overloaded — select a heavier duty size).
Calculator
From bearing catalogue
Must be less than C
Motor rpm or gear output
Formula: L10h = (10⁶ / 60×1440) × (7.00)^3.00 = 3970 hours. L10 = 343.0 million revolutions. For 8-hour single-shift operation: 2.0 years service life.
ƒFormula
L10h = (10⁶ / 60N) × (C/P)ᵖ where p = 3 (ball) | 10/3 (roller)C = basic dynamic load rating (kN, from bearing catalogue). P = equivalent dynamic bearing load (kN). N = speed (rpm). Exponent p is 3 for ball bearings and 10/3 ≈ 3.33 for roller bearings. L10h comes out in hours. For bearings in combined radial + thrust load, compute P separately using catalogue X and Y factors.
Units: Life: hours (or 10⁶ revolutions) · Loads: kN · Speed: rpm
Bearing kitne ghante chalegi? L10 kya hai?
L10 life ka matlab hai — statistically, 90% identical bearings itne hours tak chalega before fatigue failure. ISO 281 standard formula: L10h = (10⁶ / 60N) × (C/P)ᵖ. Yahan C bearing catalogue se dynamic load rating (kN), P applied load (kN), N rpm, aur p = 3 ball bearing ke liye, 10/3 roller ke liye. Load double kar do, toh life 8× kam ho jaati hai (cube law). Isliye bearing oversize karna hamesha safe hai — 20% load margin se life 1.7× badh jaati hai. SKF catalogue pe C aur C₀ (static) dono marked hote hain; L10 calculation ke liye C use karein, C₀ nahin.
Worked Examples
Standard industrial motor bearing
Problem: SKF 6205 (C = 14 kN) on an electric motor shaft at 1440 rpm with a 2 kN radial load. Expected life?
Solution: L10h = (10⁶ / (60 × 1440)) × (14/2)³ = 11.57 × 343 = 3,970 hours ≈ 0.45 years of continuous duty. For a motor that runs 8 hours/day, 250 days/year (2,000 hours/year), expect ~2 years service before fatigue.
Overloaded pump bearing
Problem: SKF 6308 (C = 41 kN) on a pump, load 20 kN at 960 rpm. Is the bearing sized right?
Solution: C/P = 41/20 = 2.05 — very tight. L10h = (10⁶ / 57600) × 2.05³ = 17.36 × 8.6 = 150 hours. Only ~1 week of continuous run. Upgrade to 6408 (C = 63 kN) — C/P = 3.15, L10h = 540 hours. For sustained operation, target C/P > 4.
Conveyor tapered roller
Problem: 30206 tapered roller bearing (C = 32 kN). Conveyor shaft at 60 rpm, load 5 kN. Life?
Solution: Roller bearing → p = 10/3. L10h = (10⁶ / 3600) × (32/5)^(10/3) = 277.8 × 512 = 142,300 hours ≈ 16 years of continuous duty. Conveyors running 12 hours/day → 32 years calendar life. For low-rpm heavy-load applications, roller bearings are significantly better than ball.
Common SKF Bearings — C (kN) + Recommended Load Range
| Bearing | Type | C (kN) | P for 10,000 h @ 1440 rpm | Typical application |
|---|---|---|---|---|
| 6203 | Ball | 9.56 | 1.2 kN | Small motors, fans |
| 6204 | Ball | 13.5 | 1.6 kN | Medium motors |
| 6205 | Ball | 14.0 | 1.7 kN | Electric motors, pumps |
| 6206 | Ball | 19.5 | 2.3 kN | Industrial motors |
| 6207 | Ball | 25.5 | 3.1 kN | Larger motors |
| 6208 | Ball | 30.7 | 3.7 kN | Heavy industrial |
| 6305 | Ball (heavy) | 22.5 | 2.7 kN | Heavy duty motor shafts |
| 6306 | Ball (heavy) | 28.1 | 3.4 kN | Pumps, compressors |
| 6308 | Ball (heavy) | 41.0 | 4.9 kN | Heavy industrial |
| 22210 | Spherical roller | 71.5 | 13.2 kN | Heavy radial + misalignment |
| 22211 | Spherical roller | 83.5 | 15.4 kN | Fan shafts, conveyors |
| 30206 | Tapered roller | 32.0 | 5.9 kN | Gearbox, axle support |
| 30208 | Tapered roller | 52.0 | 9.6 kN | Heavy axle, hub |
'P for 10,000 h @ 1440 rpm' column shows the maximum continuous load that gives ≥10,000 hours L10 life at motor speed. Multiply C by 0.12 for this quick sizing — safer than rated capacity sharing.
Need the actual parts? We stock them in Noida.
Shri Narayan Machinery LLP — C-101, Sector 9, Noida · Call +91-9811104037 · GST-invoice on every order
SKF Bearings
Deep groove, angular contact, spherical roller, tapered roller — genuine SKF.
View productsBearings Product Category
Full range including housings, adapter sleeves, and accessories.
View productsGreases & Lubricants
SKF LGMT, LGWA, LGEP greases matched to bearing operating conditions.
View productsFrequently Asked Questions — Bearing L10 Life Calculator
Need Help Picking the Right Product?
Our team at Shri Narayan Machinery has been supplying industrial parts in Noida for years. Tell us what you are building — we'll recommend the right cylinder, bearing, bolt, belt, or drill for your application.