NPS 22 Schedule 20 Pipe
22.000 in (558.8 mm) outside diameter on a 0.375 in (9.5 mm) wall, giving a 21.250 in (539.8 mm) bore and 86.61 lb/ft (128.89 kg/m) empty. ASME B36.10M.
- Nominal size
- NPS 22 (DN 550)
- Schedule
- Schedule 20
- Outside diameter
- 22.000 in (558.8 mm)
- Wall thickness
- 0.375 in (9.5 mm)
- Inside diameter
- 21.250 in (539.8 mm)
- Weight, empty
- 86.61 lb/ft (128.89 kg/m)
- Weight, water filled
- 240.36 lb/ft (357.70 kg/m)
- Flow area
- 354.656 in² (228810 mm²)
In NPS 22 this wall thickness is also designated Standard (STD). 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 this page | 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 | 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 Schedule 20 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 schedule 20 pipe?
21.250 in (539.8 mm). The outside diameter is fixed at 22.000 in (558.8 mm) by ASME B36.10M, and the 0.375 in (9.5 mm) wall takes 0.750 in off it — 0.375 in from each side — leaving that bore.
How much does NPS 22 schedule 20 pipe weigh?
86.61 lb/ft (128.89 kg/m) empty, as plain-end carbon steel. Full of water it comes to 240.36 lb/ft (357.70 kg/m), because the bore holds 18.424 US gallons per foot. One short ton of this pipe is about 23 ft.
Does NPS 22 schedule 20 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 21.250 in (539.8 mm) to match.