NPS 11 Extra Strong (XS) Pipe
11.750 in (298.4 mm) outside diameter on a 0.500 in (12.7 mm) wall, giving a 10.750 in (273.1 mm) bore and 60.08 lb/ft (89.40 kg/m) empty. ASME B36.10M.
- Nominal size
- NPS 11 (DN 275)
- Schedule
- Extra Strong (XS)
- Outside diameter
- 11.750 in (298.4 mm)
- Wall thickness
- 0.500 in (12.7 mm)
- Inside diameter
- 10.750 in (273.1 mm)
- Weight, empty
- 60.08 lb/ft (89.40 kg/m)
- Weight, water filled
- 99.42 lb/ft (147.96 kg/m)
- Flow area
- 90.763 in² (58556 mm²)
In NPS 11 this wall thickness is also designated Schedule 80. 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 11
Dimensions are given in inches, with the millimetre equivalent beneath in grey.
| Schedule | Wall thickness | Inside diameter | Weight, empty | Water (US gal/ft) |
|---|---|---|---|---|
| Sch 40 | 0.3759.52 mm | 11.000279.40 mm | 45.5667.80 kg/m | 4.937 |
| STD | 0.3759.52 mm | 11.000279.40 mm | 45.5667.80 kg/m | 4.937 |
| Sch 80 | 0.50012.70 mm | 10.750273.05 mm | 60.0889.40 kg/m | 4.715 |
| XS this page | 0.50012.70 mm | 10.750273.05 mm | 60.0889.40 kg/m | 4.715 |
Weight is plain-end carbon steel, w = 10.6802 × t × (OD − t) lb/ft.
Common questions
What is the inside diameter of NPS 11 extra strong (xs) pipe?
10.750 in (273.1 mm). The outside diameter is fixed at 11.750 in (298.4 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 11 extra strong (xs) pipe weigh?
60.08 lb/ft (89.40 kg/m) empty, as plain-end carbon steel. Full of water it comes to 99.42 lb/ft (147.96 kg/m), because the bore holds 4.715 US gallons per foot. One short ton of this pipe is about 33 ft.
Does NPS 11 extra strong (xs) pipe use special flanges or fittings?
No. Flanges and buttweld fittings are dimensioned from NPS, so NPS 11 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 10.750 in (273.1 mm) to match.