NPS 1/2 Schedule 80 Pipe
0.840 in (21.3 mm) outside diameter on a 0.147 in (3.7 mm) wall, giving a 0.546 in (13.9 mm) bore and 1.09 lb/ft (1.62 kg/m) empty. ASME B36.10M.
- Nominal size
- NPS 1/2 (DN 15)
- Schedule
- Schedule 80
- Outside diameter
- 0.840 in (21.3 mm)
- Wall thickness
- 0.147 in (3.7 mm)
- Inside diameter
- 0.546 in (13.9 mm)
- Weight, empty
- 1.09 lb/ft (1.62 kg/m)
- Weight, water filled
- 1.19 lb/ft (1.77 kg/m)
- Flow area
- 0.234 in² (151 mm²)
In NPS 1/2 this wall thickness is also designated Extra Strong (XS). That is the same pipe under another name, not a different product — but the coincidence is specific to this size and does not hold across the range.
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 | Water (US gal/ft) |
|---|---|---|---|---|
| Sch 5 | 0.0651.65 mm | 0.71018.03 mm | 0.540.80 kg/m | 0.021 |
| Sch 10 | 0.0832.11 mm | 0.67417.12 mm | 0.671.00 kg/m | 0.019 |
| Sch 40 | 0.1092.77 mm | 0.62215.80 mm | 0.851.27 kg/m | 0.016 |
| STD | 0.1092.77 mm | 0.62215.80 mm | 0.851.27 kg/m | 0.016 |
| Sch 80 this page | 0.1473.73 mm | 0.54613.87 mm | 1.091.62 kg/m | 0.012 |
| XS | 0.1473.73 mm | 0.54613.87 mm | 1.091.62 kg/m | 0.012 |
| Sch 160 | 0.1884.78 mm | 0.46411.79 mm | 1.311.95 kg/m | 0.009 |
| XXS | 0.2947.47 mm | 0.2526.40 mm | 1.712.55 kg/m | 0.003 |
Weight is plain-end carbon steel, w = 10.6802 × t × (OD − t) lb/ft.
Flanges for NPS 1/2 pipe
Flange dimensions are set by NPS and pressure class, not by schedule, so every flange below fits this pipe. The exception is the weld neck: its bore is machined to the pipe it is welded to, which for Schedule 80 means 0.546 in (13.9 mm). Order the flange to the schedule or the bores will not line up at the weld.
| Class | Flange OD | Thickness | Bolt circle | Bolting |
|---|---|---|---|---|
| Class 150 | 3.5088.90 mm | 0.4411.18 mm | 2.3860.45 mm | 4 × 1/2 in |
| Class 300 | 3.7595.25 mm | 0.5614.22 mm | 2.6266.55 mm | 4 × 1/2 in |
| Class 400 | 3.7595.25 mm | 0.5614.22 mm | 2.6266.55 mm | 4 × 1/2 in |
| Class 600 | 3.7595.25 mm | 0.5614.22 mm | 2.6266.55 mm | 4 × 1/2 in |
| Class 900 | 4.75120.65 mm | 0.8822.35 mm | 3.2582.55 mm | 4 × 3/4 in |
| Class 1500 | 4.75120.65 mm | 0.8822.35 mm | 3.2582.55 mm | 4 × 3/4 in |
| Class 2500 | 5.25133.35 mm | 1.1930.23 mm | 3.5088.90 mm | 4 × 3/4 in |
Fittings for NPS 1/2 pipe
ASME B16.9 dimensions come from NPS alone, so these figures hold for Schedule 80 exactly as they do for every other schedule in the size. Only the wall thickness has to be ordered to match.
| Fitting | Dimension | NPS 1/2 |
|---|---|---|
| 90° Long Radius Elbow | Centre-to-end A | 1.5038.10 mm |
| 45° Long Radius Elbow | Centre-to-end B | 0.6215.75 mm |
| Straight Tee | Centre-to-end C and M | 1.0025.40 mm |
| Concentric Reducer | End-to-end H | 1.5038.10 mm |
| Eccentric Reducer | End-to-end H | 1.5038.10 mm |
| Cap | Length E | 1.0025.40 mm |
Common questions
What is the inside diameter of NPS 1/2 schedule 80 pipe?
0.546 in (13.9 mm). The outside diameter is fixed at 0.840 in (21.3 mm) by ASME B36.10M, and the 0.147 in (3.7 mm) wall takes 0.294 in off it — 0.147 in from each side — leaving that bore.
How much does NPS 1/2 schedule 80 pipe weigh?
1.09 lb/ft (1.62 kg/m) empty, as plain-end carbon steel. Full of water it comes to 1.19 lb/ft (1.77 kg/m), because the bore holds 0.012 US gallons per foot. One short ton of this pipe is about 1838 ft.
Does NPS 1/2 schedule 80 pipe use special flanges or fittings?
No. Flanges and buttweld fittings are dimensioned from NPS, so NPS 1/2 hardware fits this pipe in any schedule. The one thing that does follow the schedule is the bore of a weld neck flange or a fitting end prep, which has to be 0.546 in (13.9 mm) to match.