NPS 9 Extra Strong (XS) Pipe
9.625 in (244.5 mm) outside diameter on a 0.500 in (12.7 mm) wall, giving a 8.625 in (219.1 mm) bore and 48.73 lb/ft (72.52 kg/m) empty. ASME B36.10M.
- Nominal size
- NPS 9 (DN 225)
- Schedule
- Extra Strong (XS)
- Outside diameter
- 9.625 in (244.5 mm)
- Wall thickness
- 0.500 in (12.7 mm)
- Inside diameter
- 8.625 in (219.1 mm)
- Weight, empty
- 48.73 lb/ft (72.52 kg/m)
- Weight, water filled
- 74.06 lb/ft (110.21 kg/m)
- Flow area
- 58.426 in² (37694 mm²)
In NPS 9 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 9
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 | 0.3428.69 mm | 8.941227.10 mm | 33.9150.46 kg/m | 3.262 |
| STD | 0.3428.69 mm | 8.941227.10 mm | 33.9150.46 kg/m | 3.262 |
| Sch 80 | 0.50012.70 mm | 8.625219.07 mm | 48.7372.52 kg/m | 3.035 |
| XS this page | 0.50012.70 mm | 8.625219.07 mm | 48.7372.52 kg/m | 3.035 |
Weight is plain-end carbon steel, w = 10.6802 × t × (OD − t) lb/ft.
Common questions
What is the inside diameter of NPS 9 extra strong (xs) pipe?
8.625 in (219.1 mm). The outside diameter is fixed at 9.625 in (244.5 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 9 extra strong (xs) pipe weigh?
48.73 lb/ft (72.52 kg/m) empty, as plain-end carbon steel. Full of water it comes to 74.06 lb/ft (110.21 kg/m), because the bore holds 3.035 US gallons per foot. One short ton of this pipe is about 41 ft.
Does NPS 9 extra strong (xs) pipe use special flanges or fittings?
No. Flanges and buttweld fittings are dimensioned from NPS, so NPS 9 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 8.625 in (219.1 mm) to match.