18 inch pipe (DN 450): outside diameter, wall thickness and weight by schedule
A 18 inch pipe (DN 450) has a 457 mm (18.000 in) outside diameter in every schedule: what changes is the wall, and with it the inside diameter and the weight. Designations that give the same wall share a row.
| Schedule | Wall | ID | Weight |
|---|---|---|---|
| Sch 5 / 5S | 4.19 mm (0.165 in) | 448.62 mm (17.670 in) | 46.79 kg/m (31.46 lb/ft) |
| 10S | 4.78 mm (0.188 in) | 447.44 mm (17.624 in) | 53.31 kg/m (35.80 lb/ft) |
| Sch 10 | 6.35 mm (0.250 in) | 444.30 mm (17.500 in) | 70.57 kg/m (47.44 lb/ft) |
| Sch 20 | 7.92 mm (0.312 in) | 441.16 mm (17.376 in) | 87.71 kg/m (58.99 lb/ft) |
| STD / 40S | 9.53 mm (0.375 in) | 437.94 mm (17.250 in) | 105.17 kg/m (70.65 lb/ft) |
| Sch 30 | 11.13 mm (0.438 in) | 434.74 mm (17.124 in) | 122.38 kg/m (82.23 lb/ft) |
| XS / 80S | 12.70 mm (0.500 in) | 431.60 mm (17.000 in) | 139.16 kg/m (93.54 lb/ft) |
| Sch 40 | 14.27 mm (0.562 in) | 428.46 mm (16.876 in) | 155.81 kg/m (104.76 lb/ft) |
| Sch 60 | 19.05 mm (0.750 in) | 418.90 mm (16.500 in) | 205.75 kg/m (138.30 lb/ft) |
| Sch 80 | 23.83 mm (0.938 in) | 409.34 mm (16.124 in) | 254.57 kg/m (171.08 lb/ft) |
| Sch 100 | 29.36 mm (1.156 in) | 398.28 mm (15.688 in) | 309.64 kg/m (208.15 lb/ft) |
| Sch 120 | 34.93 mm (1.375 in) | 387.14 mm (15.250 in) | 363.58 kg/m (244.37 lb/ft) |
| Sch 140 | 39.67 mm (1.562 in) | 377.66 mm (14.876 in) | 408.28 kg/m (274.48 lb/ft) |
| Sch 160 | 45.24 mm (1.781 in) | 366.52 mm (14.438 in) | 459.39 kg/m (308.79 lb/ft) |
Plain-end weight of carbon steel pipe, by the standard's own formula: 10.69 × (D − t) × t in lb/ft, with D and t in inches (0.0246615 × (D − t) × t in kg/m, in mm). Austenitic stainless weighs about 2% more.
Lay out on 18 inch pipe
The outside diameter and the wall of the chosen schedule go to the calculator, which opens with them filled in and draws without an account.
Questions
- What is the outside diameter of 18 inch pipe?
- 457 mm (18.000 in), in any schedule: it is the DN 450 pipe of ASME B36.10M. The wall changes with the schedule, and the inside diameter with it.
- What is the wall thickness of 18 inch schedule 40 pipe?
- 14.27 mm (0.562 in), with an inside diameter of 428.46 mm (16.876 in); carbon steel pipe weighs 155.81 kg/m (104.76 lb/ft).
- What is the difference between schedule 40 and 80 in 18 inch pipe?
- The wall: 14.27 mm (0.562 in) in schedule 40 and 23.83 mm (0.938 in) in 80. The outside diameter is the same, so schedule 80 has the smaller bore -- 409.34 mm (16.124 in) against 428.46 mm (16.876 in) -- and weighs 254.57 kg/m (171.08 lb/ft) against 155.81 kg/m (104.76 lb/ft).
Flanges for 18 inch pipe
By schedule
- Schedule 5
- Schedule 5S
- Schedule 10
- Schedule 10S
- Schedule 20
- Schedule 30
- Schedule 40
- STD
- Schedule 40S
- Schedule 60
- Schedule 80
- XS
- Schedule 80S
- Schedule 100
- Schedule 120
- Schedule 140
- Schedule 160
- XXS