20 inch (DN 500) pipe dimensions & weight
20 inch (DN 500) steel pipe has an outside diameter of 508.0 mm (20.000 in) in every schedule. Below: wall thickness, inside diameter, weight per metre and water capacity for each ASME B36.10M / B36.19M schedule.
| Schedule | Wall (mm) | Wall (in) | ID (mm) | CS kg/m | CS lb/ft | SS 304 kg/m | Water L/m |
|---|---|---|---|---|---|---|---|
| Sch 5S | 4.78 | 0.188 | 498.44 | 59.32 | 39.86 | 59.92 | 195.13 |
| Sch 10S | 5.54 | 0.218 | 496.92 | 68.64 | 46.13 | 69.34 | 193.94 |
| Sch 10 | 6.35 | 0.250 | 495.30 | 78.55 | 52.79 | 79.35 | 192.68 |
| Sch 20 | 9.53 | 0.375 | 488.94 | 117.15 | 78.72 | 118.34 | 187.76 |
| Sch 30 | 12.70 | 0.500 | 482.60 | 155.12 | 104.24 | 156.70 | 182.92 |
| STD | 9.53 | 0.375 | 488.94 | 117.15 | 78.72 | 118.34 | 187.76 |
| Sch 40 | 15.09 | 0.594 | 477.82 | 183.42 | 123.26 | 185.29 | 179.32 |
| Sch 60 | 20.62 | 0.812 | 466.76 | 247.83 | 166.54 | 250.36 | 171.11 |
| XS | 12.70 | 0.500 | 482.60 | 155.12 | 104.24 | 156.70 | 182.92 |
| Sch 80 | 26.19 | 1.031 | 455.62 | 311.17 | 209.11 | 314.34 | 163.04 |
| Sch 100 | 32.54 | 1.281 | 442.92 | 381.53 | 256.39 | 385.42 | 154.08 |
| Sch 120 | 38.10 | 1.500 | 431.80 | 441.49 | 296.68 | 445.99 | 146.44 |
| Sch 140 | 44.45 | 1.750 | 419.10 | 508.11 | 341.45 | 513.29 | 137.95 |
| Sch 160 | 50.01 | 1.969 | 407.98 | 564.81 | 379.55 | 570.57 | 130.73 |
CS = carbon steel (7.85 g/cm³). SS 304 at 7.93 g/cm³; for 316 multiply CS weight by 1.017. Water capacity = internal volume per metre.
Matching 20" flanges and fittings
| Class 150 flange | OD 700 mm · thk 41.3 mm · PCD 635.0 mm · 20 × 1-1/8" bolts |
| Class 300 flange | OD 775 mm · thk 62.0 mm · PCD 685.8 mm · 24 × 1-1/4" bolts |
| B16.9 fittings | 90° LR 762 mm · 45° LR 318 mm · 90° SR 508 mm · tee 381 mm · reducer 508 mm · cap 229 mm |
Full tables: Class 150 · Class 300 · B16.9 fittings.
Frequently asked questions
What is the OD of 20 inch pipe?
20 inch (DN 500) pipe has an outside diameter of 508.0 mm (20.000 in), regardless of schedule.
What is the wall thickness of 20 inch Schedule 40 pipe?
15.09 mm (0.594 in), giving an inside diameter of 477.82 mm.
How much does 20 inch Schedule 40 pipe weigh?
About 183.42 kg/m (123.26 lb/ft) in carbon steel, or 1100.5 kg for a 6 m length.
What is the wall thickness of 20 inch Schedule 80 pipe?
26.19 mm, with an inside diameter of 455.62 mm and weight of 311.17 kg/m.
Last updated 2026-11-02