NPS 1/2 Pipe Dimensions
Outside diameter 0.840 in (21.3 mm) — fixed across every schedule. 8 wall thicknesses from ASME B36.10M, with bore, plain-end weight and flow area for each.
- Nominal size
- NPS 1/2
- Metric designator
- DN 15
- Outside diameter
- 0.840 in (21.3 mm)
- Schedules listed
- 8
- Standard weight wall
- 0.109 in (2.8 mm)
- Extra strong wall
- 0.147 in (3.7 mm)
Every schedule in NPS 1/2
Dimensions are given in inches, with the millimetre equivalent beneath in grey.
| Schedule | Wall thickness | Inside diameter | Weight, empty | Flow area (in²) | Water (US gal/ft) |
|---|---|---|---|---|---|
| Sch 5 | 0.0651.65 mm | 0.71018.03 mm | 0.540.80 kg/m | 0.40 | 0.021 |
| Sch 10 | 0.0832.11 mm | 0.67417.12 mm | 0.671.00 kg/m | 0.36 | 0.019 |
| Sch 40 | 0.1092.77 mm | 0.62215.80 mm | 0.851.27 kg/m | 0.30 | 0.016 |
| STD | 0.1092.77 mm | 0.62215.80 mm | 0.851.27 kg/m | 0.30 | 0.016 |
| Sch 80 | 0.1473.73 mm | 0.54613.87 mm | 1.091.62 kg/m | 0.23 | 0.012 |
| XS | 0.1473.73 mm | 0.54613.87 mm | 1.091.62 kg/m | 0.23 | 0.012 |
| Sch 160 | 0.1884.78 mm | 0.46411.79 mm | 1.311.95 kg/m | 0.17 | 0.009 |
| XXS | 0.2947.47 mm | 0.2526.40 mm | 1.712.55 kg/m | 0.05 | 0.003 |
Weight is calculated for carbon steel as w = 10.6802 × t × (OD − t) lb/ft and is the plain-end weight, excluding coatings, linings and fittings.
Standard weight equals Schedule 40 in this size. Extra strong equals Schedule 80.
This size, schedule by schedule
A page for each combination, with bore, weight, water capacity and the matching flange and fitting data.
This size in a schedule chart
Common questions
What is the outside diameter of NPS 1/2 pipe?
NPS 1/2 pipe has an outside diameter of 0.840 in (21.3 mm). That outside diameter is fixed: it is identical in every schedule, and only the wall thickness — and therefore the bore — changes from one schedule to the next.
How much does NPS 1/2 schedule 40 pipe weigh?
0.85 lb/ft (1.27 kg/m) as plain-end carbon steel, on a wall thickness of 0.109 in (2.8 mm).
What is the metric equivalent of NPS 1/2?
DN 15. DN is a dimensionless designator, not a measurement — DN 15 pipe does not measure 15 mm anywhere. Its actual outside diameter is 21.3 mm.