NPS 4 1/2 Standard (STD) Pipe
5.000 in (127.0 mm) outside diameter on a 0.247 in (6.3 mm) wall, giving a 4.506 in (114.5 mm) bore and 12.54 lb/ft (18.66 kg/m) empty. ASME B36.10M.
- Nominal size
- NPS 4 1/2 (DN 115)
- Schedule
- Standard (STD)
- Outside diameter
- 5.000 in (127.0 mm)
- Wall thickness
- 0.247 in (6.3 mm)
- Inside diameter
- 4.506 in (114.5 mm)
- Weight, empty
- 12.54 lb/ft (18.66 kg/m)
- Weight, water filled
- 19.45 lb/ft (28.95 kg/m)
- Flow area
- 15.947 in² (10288 mm²)
In NPS 4 1/2 this wall thickness is also designated Schedule 40. 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 4 1/2
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 | 0.2476.27 mm | 4.506114.45 mm | 12.5418.66 kg/m | 0.828 |
| STD this page | 0.2476.27 mm | 4.506114.45 mm | 12.5418.66 kg/m | 0.828 |
| Sch 80 | 0.3559.02 mm | 4.290108.97 mm | 17.6126.21 kg/m | 0.751 |
| XS | 0.3559.02 mm | 4.290108.97 mm | 17.6126.21 kg/m | 0.751 |
| XXS | 0.71018.03 mm | 3.58090.93 mm | 32.5348.41 kg/m | 0.523 |
Weight is plain-end carbon steel, w = 10.6802 × t × (OD − t) lb/ft.
Common questions
What is the inside diameter of NPS 4 1/2 standard (std) pipe?
4.506 in (114.5 mm). The outside diameter is fixed at 5.000 in (127.0 mm) by ASME B36.10M, and the 0.247 in (6.3 mm) wall takes 0.494 in off it — 0.247 in from each side — leaving that bore.
How much does NPS 4 1/2 standard (std) pipe weigh?
12.54 lb/ft (18.66 kg/m) empty, as plain-end carbon steel. Full of water it comes to 19.45 lb/ft (28.95 kg/m), because the bore holds 0.828 US gallons per foot. One short ton of this pipe is about 160 ft.
Does NPS 4 1/2 standard (std) pipe use special flanges or fittings?
No. Flanges and buttweld fittings are dimensioned from NPS, so NPS 4 1/2 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 4.506 in (114.5 mm) to match.