Circular Ducts - Dimensions
Circular Ducts Dimensions - Metric Units
Common circular ductwork sizes used in air handling ventilation systems:
| Nominal Diameter (mm) | Outside Diameter (mm) | Inside Diameter (mm) |
|---|---|---|
| 63 | 63 - 63.5 | 61.8 - 62.3 |
| 80 | 80 - 80.5 | 78.8 - 79.3 |
| 100 | 100 - 100.5 | 98.8 - 99.3 |
| 125 | 125 - 125.5 | 123.8 - 124.3 |
| 160 | 160 - 160.6 | 158.7 - 159.3 |
| 200 | 200 - 200.7 | 198.6 - 199.3 |
| 250 | 250 - 250.8 | 248.5 - 249.3 |
| 315 | 315 - 315.9 | 313.4 - 314.3 |
| 400 | 400 - 401.0 | 398.3 - 399.3 |
| 500 | 500 - 501.1 | 498.2 - 499.3 |
| 630 | 630 - 631.2 | 628.1 - 629.3 |
| 800 | 800 - 801.6 | 798.0 - 799.3 |
| 1000 | 1000 - 1002.0 | 997.9 - 999.3 |
| 1250 | 1250 - 1252.5 | 1247.8 - 1249.3 |
Circular Galvanized Steel Ducts - Areas and Weights - Imperial Units
| Diameter (inches) | Surface Area (ft2/ft) | Gage | ||
|---|---|---|---|---|
| 26 | 24 | 22 | ||
| Weight (lbs/ft) | ||||
| 4 | 1.05 | 1.02 | 1.36 | 1.59 |
| 5 | 1.31 | 1.25 | 1.67 | 1.95 |
| 6 | 1.57 | 1.49 | 1.98 | 2.32 |
| 7 | 1.83 | 1.72 | 2.30 | 2.69 |
| 8 | 2.09 | 1.96 | 2.61 | 3.06 |
| 9 | 2.36 | 2.20 | 2.93 | 3.42 |
| 10 | 2.62 | 2.51 | 3.34 | 3.91 |
| 11 | 2.88 | 2.74 | 3.66 | 4.28 |
| 12 | 3.14 | 2.98 | 3.97 | 4.64 |
| 13 | 3.40 | 3.21 | 4.28 | 5.01 |
| 14 | 3.67 | 3.45 | 4.60 | 5.38 |
| 15 | 3.93 | 3.68 | 4.91 | 5.75 |
| 16 | 4.19 | 3.92 | 5.23 | 6.12 |
| 17 | 4.45 | 4.16 | 5.54 | 6.48 |
| 18 | 4.72 | 4.39 | 5.85 | 6.85 |
| 19 | 4.98 | 4.63 | 6.17 | 7.22 |
| 20 | 5.24 | 4.94 | 6.58 | 7.70 |
| 21 | 5.50 | 5.18 | 6.90 | 8.07 |
| 22 | 5.75 | 5.41 | 7.21 | 8.44 |
| 23 | 6.02 | 5.64 | 7.53 | 8.80 |
| 24 | 6.28 | 5.88 | 7.84 | 9.17 |
| 25 | 6.54 | 6.12 | 8.15 | 9.54 |
| 26 | 6.80 | 6.35 | 8.47 | 9.91 |
| 27 | 7.07 | 8.78 | 10.27 | 12.47 |
| 28 | 7.33 | 9.10 | 10.64 | 12.92 |
| 29 | 7.59 | 9.41 | 11.01 | 13.36 |
| 30 | 7.85 | 9.83 | 11.50 | 13.95 |
| 31 | 8.11 | 10.14 | 11.86 | 14.40 |
| 32 | 8.38 | 10.45 | 12.23 | 14.84 |
| 33 | 8.65 | 10.77 | 12.67 | 15.29 |
| 34 | 8.91 | 11.08 | 12.96 | 15.75 |
| 35 | 9.17 | 11.40 | 13.33 | 16.18 |
| 36 | 9.43 | 11.71 | 13.70 | 16.63 |
| 37 | 9.69 | 12.02 | 14.07 | 17.07 |
| 38 | 9.95 | 12.34 | 14.44 | 17.52 |
| 39 | 10.21 | 12.65 | 14.80 | 17.97 |
| 40 | 10.47 | 13.07 | 15.29 | 18.55 |
| 41 | 10.73 | 13.39 | 15.66 | 19.00 |
| 42 | 10.99 | 13.70 | 16.02 | 19.45 |
| 43 | 11.26 | 14.01 | 16.39 | 19.89 |
| 44 | 11.52 | 14.32 | 16.76 | 20.34 |
Related Topics
• Ventilation Systems
Design of systems for ventilation and air handling - air change rates, ducts and pressure drops, charts and diagrams and more.
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