Across Flat to Diameter Calculator
Across Flat to Diameter Table
| Across Flats (AF) (mm) | Estimated Diameter (mm) |
|---|---|
| 10 | 11.55 |
| 12 | 13.86 |
| 14 | 16.17 |
| 16 | 18.48 |
| 18 | 20.79 |
| 20 | 23.10 |
| 22 | 25.40 |
| 24 | 27.71 |
| 27 | 31.18 |
| 30 | 34.65 |
| 32 | 36.96 |
| 36 | 41.58 |
| 41 | 47.37 |
| 46 | 53.15 |
| 50 | 57.74 |
How to Use This Table
- Find the Across Flats (AF) value → Measure the distance between two opposite flat sides of a hexagon.
- Look up the corresponding diameter → This is the estimated circular equivalent.
- Use this in machining, bolt selection, or fitting calculations.
How is Diameter Calculated?
The formula used: Diameter=Across Flats (AF)0.866\text{Diameter} = \frac{\text{Across Flats (AF)}}{0.866}Diameter=0.866Across Flats (AF)
Where:
- Across Flats (AF) = The measured distance between two opposite flat sides.
- 0.866 = The mathematical conversion factor for a perfect hexagon.
Key Takeaways
- Larger across-flat values result in larger equivalent diameters.
- Common in bolt head and nut size measurements.
- Used in machining, engineering, and manufacturing applications.
- Helps in converting hexagonal dimensions to round equivalents.