NPS 3 1/2 Pipe Dimensions
Outside diameter 4.000 in (101.6 mm) — fixed across every schedule. 7 wall thicknesses from ASME B36.10M, with bore, plain-end weight and flow area for each.
- Nominal size
- NPS 3 1/2
- Metric designator
- DN 90
- Outside diameter
- 4.000 in (101.6 mm)
- Schedules listed
- 7
- Standard weight wall
- 0.226 in (5.7 mm)
- Extra strong wall
- 0.318 in (8.1 mm)
Every schedule in NPS 3 1/2
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 5 | 0.0832.11 mm | 3.83497.38 mm | 3.475.17 kg/m | 11.55 | 0.600 |
| Sch 10 | 0.1203.05 mm | 3.76095.50 mm | 4.977.40 kg/m | 11.10 | 0.577 |
| Sch 40 | 0.2265.74 mm | 3.54890.12 mm | 9.1113.56 kg/m | 9.89 | 0.514 |
| STD | 0.2265.74 mm | 3.54890.12 mm | 9.1113.56 kg/m | 9.89 | 0.514 |
| Sch 80 | 0.3188.08 mm | 3.36485.45 mm | 12.5118.61 kg/m | 8.89 | 0.462 |
| XS | 0.3188.08 mm | 3.36485.45 mm | 12.5118.61 kg/m | 8.89 | 0.462 |
| XXS | 0.63616.15 mm | 2.72869.29 mm | 22.8534.00 kg/m | 5.84 | 0.304 |
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 3 1/2 pipe?
NPS 3 1/2 pipe has an outside diameter of 4.000 in (101.6 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 3 1/2 schedule 40 pipe weigh?
9.11 lb/ft (13.56 kg/m) as plain-end carbon steel, on a wall thickness of 0.226 in (5.7 mm).
What is the metric equivalent of NPS 3 1/2?
DN 90. DN is a dimensionless designator, not a measurement — DN 90 pipe does not measure 90 mm anywhere. Its actual outside diameter is 101.6 mm.