NPS 22 Extra Strong (XS) Pipe
22.000 in (558.8 mm) outside diameter on a 0.500 in (12.7 mm) wall, giving a 21.000 in (533.4 mm) bore and 114.81 lb/ft (170.86 kg/m) empty. ASME B36.10M.
- Nominal size
- NPS 22 (DN 550)
- Schedule
- Extra Strong (XS)
- Outside diameter
- 22.000 in (558.8 mm)
- Wall thickness
- 0.500 in (12.7 mm)
- Inside diameter
- 21.000 in (533.4 mm)
- Weight, empty
- 114.81 lb/ft (170.86 kg/m)
- Weight, water filled
- 264.97 lb/ft (394.32 kg/m)
- Flow area
- 346.361 in² (223458 mm²)
In NPS 22 this wall thickness is also designated Schedule 30. 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 22
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 | 0.1884.78 mm | 21.624549.25 mm | 43.8065.18 kg/m | 19.078 |
| Sch 10 | 0.2185.54 mm | 21.564547.73 mm | 50.7175.47 kg/m | 18.972 |
| Sch 20 | 0.3759.52 mm | 21.250539.75 mm | 86.61128.89 kg/m | 18.424 |
| Sch 30 | 0.50012.70 mm | 21.000533.40 mm | 114.81170.86 kg/m | 17.993 |
| STD | 0.3759.52 mm | 21.250539.75 mm | 86.61128.89 kg/m | 18.424 |
| Sch 60 | 0.87522.22 mm | 20.250514.35 mm | 197.42293.79 kg/m | 16.731 |
| Sch 80 | 1.12528.57 mm | 19.750501.65 mm | 250.82373.26 kg/m | 15.915 |
| XS this page | 0.50012.70 mm | 21.000533.40 mm | 114.81170.86 kg/m | 17.993 |
| Sch 100 | 1.37534.92 mm | 19.250488.95 mm | 302.88450.74 kg/m | 15.119 |
| Sch 120 | 1.62541.27 mm | 18.750476.25 mm | 353.61526.24 kg/m | 14.344 |
| Sch 140 | 1.87547.62 mm | 18.250463.55 mm | 403.01599.74 kg/m | 13.589 |
| Sch 160 | 2.12553.97 mm | 17.750450.85 mm | 451.07671.27 kg/m | 12.855 |
Weight is plain-end carbon steel, w = 10.6802 × t × (OD − t) lb/ft.
Fittings for NPS 22 pipe
ASME B16.9 dimensions come from NPS alone, so these figures hold for Extra Strong (XS) exactly as they do for every other schedule in the size. Only the wall thickness has to be ordered to match.
| Fitting | Dimension | NPS 22 |
|---|---|---|
| 90° Long Radius Elbow | Centre-to-end A | 33.00838.20 mm |
| 90° Short Radius Elbow | Centre-to-end A | 22.00558.80 mm |
| 45° Long Radius Elbow | Centre-to-end B | 13.75349.25 mm |
| Straight Tee | Centre-to-end C and M | 16.50419.10 mm |
| Reducing Tee | Run centre-to-end C | 16.50419.10 mm |
| Concentric Reducer | End-to-end H | 20.00508.00 mm |
| Eccentric Reducer | End-to-end H | 20.00508.00 mm |
| Cap | Length E | 10.00254.00 mm |
Common questions
What is the inside diameter of NPS 22 extra strong (xs) pipe?
21.000 in (533.4 mm). The outside diameter is fixed at 22.000 in (558.8 mm) by ASME B36.10M, and the 0.500 in (12.7 mm) wall takes 1.000 in off it — 0.500 in from each side — leaving that bore.
How much does NPS 22 extra strong (xs) pipe weigh?
114.81 lb/ft (170.86 kg/m) empty, as plain-end carbon steel. Full of water it comes to 264.97 lb/ft (394.32 kg/m), because the bore holds 17.993 US gallons per foot. One short ton of this pipe is about 17 ft.
Does NPS 22 extra strong (xs) pipe use special flanges or fittings?
No. Flanges and buttweld fittings are dimensioned from NPS, so NPS 22 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 21.000 in (533.4 mm) to match.