NPS 3/8 Extra Strong (XS) Pipe
0.675 in (17.1 mm) outside diameter on a 0.126 in (3.2 mm) wall, giving a 0.423 in (10.7 mm) bore and 0.74 lb/ft (1.10 kg/m) empty. ASME B36.10M.
- Nominal size
- NPS 3/8 (DN 10)
- Schedule
- Extra Strong (XS)
- Outside diameter
- 0.675 in (17.1 mm)
- Wall thickness
- 0.126 in (3.2 mm)
- Inside diameter
- 0.423 in (10.7 mm)
- Weight, empty
- 0.74 lb/ft (1.10 kg/m)
- Weight, water filled
- 0.80 lb/ft (1.19 kg/m)
- Flow area
- 0.141 in² (91 mm²)
In NPS 3/8 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 3/8
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 | 0.0491.24 mm | 0.57714.66 mm | 0.330.49 kg/m | 0.014 |
| Sch 10 | 0.0651.65 mm | 0.54513.84 mm | 0.420.63 kg/m | 0.012 |
| Sch 40 | 0.0912.31 mm | 0.49312.52 mm | 0.570.84 kg/m | 0.010 |
| STD | 0.0912.31 mm | 0.49312.52 mm | 0.570.84 kg/m | 0.010 |
| Sch 80 | 0.1263.20 mm | 0.42310.74 mm | 0.741.10 kg/m | 0.007 |
| XS this page | 0.1263.20 mm | 0.42310.74 mm | 0.741.10 kg/m | 0.007 |
Weight is plain-end carbon steel, w = 10.6802 × t × (OD − t) lb/ft.
Common questions
What is the inside diameter of NPS 3/8 extra strong (xs) pipe?
0.423 in (10.7 mm). The outside diameter is fixed at 0.675 in (17.1 mm) by ASME B36.10M, and the 0.126 in (3.2 mm) wall takes 0.252 in off it — 0.126 in from each side — leaving that bore.
How much does NPS 3/8 extra strong (xs) pipe weigh?
0.74 lb/ft (1.10 kg/m) empty, as plain-end carbon steel. Full of water it comes to 0.80 lb/ft (1.19 kg/m), because the bore holds 0.007 US gallons per foot. One short ton of this pipe is about 2707 ft.
Does NPS 3/8 extra strong (xs) pipe use special flanges or fittings?
No. Flanges and buttweld fittings are dimensioned from NPS, so NPS 3/8 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 0.423 in (10.7 mm) to match.