NPS 9 Pipe Dimensions
Outside diameter 9.625 in (244.5 mm) — fixed across every schedule. 4 wall thicknesses from ASME B36.10M, with bore, plain-end weight and flow area for each.
- Nominal size
- NPS 9
- Metric designator
- DN 225
- Outside diameter
- 9.625 in (244.5 mm)
- Schedules listed
- 4
- Standard weight wall
- 0.342 in (8.7 mm)
- Extra strong wall
- 0.500 in (12.7 mm)
Every schedule in NPS 9
Dimensions are given in inches, with the millimetre equivalent beneath in grey.
| Schedule | Wall thickness | Inside diameter | Weight, empty | Flow area (in²) | Water (US gal/ft) |
|---|---|---|---|---|---|
| Sch 40 | 0.3428.69 mm | 8.941227.10 mm | 33.9150.46 kg/m | 62.79 | 3.262 |
| STD | 0.3428.69 mm | 8.941227.10 mm | 33.9150.46 kg/m | 62.79 | 3.262 |
| Sch 80 | 0.50012.70 mm | 8.625219.07 mm | 48.7372.52 kg/m | 58.43 | 3.035 |
| XS | 0.50012.70 mm | 8.625219.07 mm | 48.7372.52 kg/m | 58.43 | 3.035 |
Weight is calculated for carbon steel as w = 10.6802 × t × (OD − t) lb/ft and is the plain-end weight, excluding coatings, linings and fittings.
Standard weight equals Schedule 40 in this size. Extra strong equals Schedule 80.
This size, schedule by schedule
A page for each combination, with bore, weight, water capacity and the matching flange and fitting data.
This size in a schedule chart
Common questions
What is the outside diameter of NPS 9 pipe?
NPS 9 pipe has an outside diameter of 9.625 in (244.5 mm). That outside diameter is fixed: it is identical in every schedule, and only the wall thickness — and therefore the bore — changes from one schedule to the next.
How much does NPS 9 schedule 40 pipe weigh?
33.91 lb/ft (50.46 kg/m) as plain-end carbon steel, on a wall thickness of 0.342 in (8.7 mm).
What is the metric equivalent of NPS 9?
DN 225. DN is a dimensionless designator, not a measurement — DN 225 pipe does not measure 225 mm anywhere. Its actual outside diameter is 244.5 mm.