Pipe Schedule Chart, Pipe Size Chart, NPS Pipe Diameter
| Nominal Size | OD | Wall Thickness, SCH | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NPS | DN | mm | 5S | 10S | 10 | 20 | 30 | 40S | STD | 40 | 60 | 80S | XS | 80 | 100 | 120 | 140 | 160 | XXS |
| 1∕8 | 6 | 10.3 | – | 1.24 | – | – | – | 1.73 | 1.73 | 1.73 | – | 2.41 | 2.41 | 2.41 | – | – | – | – | – |
| 1∕4 | 8 | 13.7 | – | 1.65 | – | – | – | 2.24 | 2.24 | 2.24 | – | 3.02 | 3.02 | 3.02 | – | – | – | – | – |
| 3∕8 | 10 | 17.2 | – | 1.65 | – | – | – | 2.31 | 2.31 | 2.31 | – | 3.2 | 3.2 | 3.2 | – | – | – | – | – |
| 1∕2 | 15 | 21.3 | 1.65 | 2.11 | – | – | – | 2.77 | 2.77 | 2.77 | – | 3.73 | 3.73 | 3.73 | – | – | – | 4.78 | 7.47 |
| 3∕4 | 20 | 26.7 | 1.65 | 2.11 | – | – | – | 2.87 | 2.87 | 2.87 | – | 3.91 | 3.91 | 3.91 | – | – | – | 5.56 | 7.82 |
| 1 | 25 | 33.4 | 1.65 | 2.77 | – | – | – | 3.38 | 3.38 | 3.38 | – | 4.55 | 4.55 | 4.55 | – | – | – | 6.35 | 9.09 |
| 1 1∕4 | 32 | 42.2 | 1.65 | 2.77 | – | – | – | 3.56 | 3.56 | 3.56 | – | 4.85 | 4.85 | 4.85 | – | – | – | 6.35 | 9.7 |
| 1 1∕2 | 40 | 48.3 | 1.65 | 2.77 | – | – | – | 3.68 | 3.68 | 3.68 | – | 5.08 | 5.08 | 5.08 | – | – | – | 7.14 | 10.15 |
| 2 | 50 | 60.3 | 1.65 | 2.77 | – | – | – | 3.91 | 3.91 | 3.91 | – | 5.54 | 5.54 | 5.54 | – | – | – | 8.74 | 11.07 |
| 2 1∕2 | 65 | 73 | 2.11 | 3.05 | – | – | – | 5.16 | 5.16 | 5.16 | – | 7.01 | 7.01 | 7.01 | – | – | – | 9.53 | 14.02 |
| 3 | 80 | 88.9 | 2.11 | 3.05 | – | – | – | 5.49 | 5.49 | 5.49 | – | 7.62 | 7.62 | 7.62 | – | – | – | 11.13 | 15.24 |
| 3 1∕2 | 90 | 101.6 | 2.11 | 3.05 | – | – | – | 5.74 | 5.74 | 5.74 | – | 8.08 | 8.08 | 8.08 | – | – | – | – | – |
| 4 | 100 | 114.3 | 2.11 | 3.05 | – | – | – | 6.02 | 6.02 | 6.02 | – | 8.56 | 8.56 | 8.56 | – | 11.13 | – | 13.49 | 17.12 |
| 5 | 125 | 141.3 | 2.77 | 3.4 | – | – | – – | 6.55 | 6.55 | 6.55 | – | 9.53 | 9.53 | 9.53 | – | 12.7 | – | 15.88 | 19.05 |
| 6 | 150 | 168.3 | 2.77 | 3.4 | – | – | – | 7.11 | 7.11 | 7.11 | – | 10.97 | 10.97 | 10.97 | – | 14.27 | – | 18.26 | 21.95 |
| 8 | 200 | 219.1 | 2.77 | 3.76 | – | 6.35 | 7.04 | 8.18 | 8.18 | 8.18 | 10.31 | 12.7 | 12.7 | 12.7 | 15.09 | 18.26 | 20.62 | 23.01 | 22.23 |
| 10 | 250 | 273.1 | 3.4 | 4.19 | – | 6.35 | 7.8 | 9.27 | 9.27 | 9.27 | 12.7 | 12.7 | 12.7 | 15.09 | 18.26 | 21.44 | 25.4 | 28.58 | 25.4 |
| 12 | 300 | 323.9 | 3.96 | 4.57 | – | 6.35 | 8.38 | 9.53 | 9.53 | 10.31 | 14.27 | 12.7 | 12.7 | 17.48 | 21.44 | 25.4 | 28.58 | 33.32 | 25.4 |
| 14 | 350 | 355.6 | 3.96 | 4.78 | 6.35 | 7.92 | 9.53 | – | 9.53 | 11.13 | 15.09 | – | 12.7 | 19.05 | 23.83 | 27.79 | 31.75 | 35.71 | – |
| 16 | 400 | 406.4 | 4.19 | 4.78 | 6.35 | 7.92 | 9.53 | – | 9.53 | 12.7 | 16.66 | – | 12.7 | 21.44 | 26.19 | 30.96 | 36.53 | 40.49 | – |
| 18 | 450 | 457.2 | 4.19 | 4.78 | 6.35 | 7.92 | 11.13 | – | 9.53 | 14.27 | 19.05 | – | 12.7 | 23.83 | 29.36 | 34.93 | 39.67 | 45.24 | – |
| 20 | 500 | 508 | 4.78 | 5.54 | 6.35 | 9.53 | 12.7 | – | 9.53 | 15.09 | 20.62 | – | 12.7 | 26.19 | 32.54 | 38.1 | 44.45 | 50.01 | – |
| 22 | 550 | 558.8 | 4.78 | 5.54 | 6.35 | 9.53 | 12.7 | – | 9.53 | – | 22.23 | – | 12.7 | 28.58 | 34.93 | 41.28 | 47.63 | 53.98 | – |
| 24 | 600 | 609.6 | 5.54 | 6.35 | 6.35 | 9.53 | 14.27 | – | 9.53 | 17.48 | 24.61 | – | 12.7 | 30.96 | 38.89 | 46.02 | 52.37 | 59.54 | – |
| 26 | 650 | 660.4 | – | – | 7.92 | 12.7 | – | – | 9.53 | – | – | – | 12.7 | – | – | – | – | – | – |
| 28 | 700 | 711.2 | – | – | 7.92 | 12.7 | 15.88 | – | 9.53 | – | – | – | 12.7 | – | – | – | – | – | – |
| 30 | 750 | 762 | 6.35 | 7.92 | 7.92 | 12.7 | 15.88 | – | 9.53 | – | – | – | 12.7 | – | – | – | – | – | – |
| 32 | 800 | 812.8 | – | – | 7.92 | 12.7 | 15.88 | 17.48 | 9.53 | 17.48 | – | – | 12.7 | – | – | – | – | – | – |
| 34 | 850 | 863.6 | – | – | 7.92 | 12.7 | 15.88 | 17.48 | 9.53 | 17.48 | – | – | 12.7 | – | – | – | – | – | – |
| 36 | 900 | 914.4 | – | – | 7.92 | 12.7 | 15.88 | 19.05 | 9.53 | 19.05 | – | – | 12.7 | – | – | – | – | – | – |
| 38 | 950 | 965.2 | – | – | – | – | – | – | 9.53 | – | – | – | 12.7 | – | – | – | – | – | – |
| 40 | 1000 | 1016 | – | – | – | – | – | – | 9.53 | – | – | – | |||||||
From above data chart, pipe sizes are determined by NPS and Schedule Number based on ASME/ANSI B 36.10 Welded and Seamless Wrought Steel Pipe and ASME/ANSI B36.19 Stainless Steel Pipe, some points should be noted below:
- For a given NPS, the outside diameter stays constant and the wall thickness increases with a larger schedule number. The inside diameter will depend upon the pipe wall thickness specified by the schedule number.
- From NPS ⅛ to 12 inches, the NPS and OD values are different.
- For NPS 14 inches and above, the NPS and OD values are equal, and the NPS pipe size is the actual outside diameter.
- From NPS 12 to NPS 22 the wall thicknesses in some cases are different. Pipes with the suffix “S” have in that range of thinner wall thickness.
- For NPS ≥ 4, the related DN is equal to the NPS number multiplied by 25.
Pipe Schedule
The pipe schedule is the way pipe wall thickness is designated. Pipe wall thickness is expressed in “schedules”, referred to as pipe schedules.
While the Nominal Pipe Size identifies the outside diameter of the pipe, more information is needed to identify specific pipes. A pipe’s schedule is the thickness of the pipe wall, which directly affects the interior dimension and weight of the pipe. Wall thickness is important because it determines the amount of internal pressure that the pipe can withstand. The schedule number is roughly calculated as: Schedule = 1000 x (P/S) where P is the internal service pressure of the pipe (psig) and S is the ultimate tensile strength of the pipe material (psi).
The two most common schedule sizes seen in buildings are Schedule 40 and Schedule 80. However, some process piping, utility facilities, and civil piping may require higher schedule numbers depending on the pressures used.
Originally there are three pipe wall thicknesses in use
- Standard (STD)
- Extra Strong (XS)
- Double Extra Strong (XXS)
Today, Schedule numbers for wall thicknesses are invented.
SCHEDULE 5, 5S, 10, 10S, 20, 30, 40, 40S, 60, 80, 80S, 100, 120, 140, 160, STD, XS and XXS.
Stainless Steel pipe schedules append an “S” to the end of the schedule number, for instance, Schedule 40S.
Nominal Pipe Size (NPS)
Nominal Pipe Sizing (NPS) is a North American standard for identifying pipe sizes, it gives the approximate inside diameter or nominal bore of a pipe. The European designation equivalent to NPS is DN (diamètre nominal/nominal diameter/Durchmesser nach Norm). All pipes are specified using the NPS (or DN) and schedule numbers, it is the schedule number that determines the approximate inside diameter.
Technically, the NPS is non-dimensional and only roughly refers to the diameter of the pipe. However, from NPS 14 and above, the NPS value matches the outside diameter of the pipe. Nominal Pipe Sizes apply to all materials of pipe. When specific pipes are specified, the NPS, Schedule, and material are required.
Pipe Inside Diameter
The inside diameter of the pipe is determined by NPS and pipe schedule, while the standardized NPS outside diameters are unchanged, the Schedule number is increased, inside diameter is reduced.
Pipes are designed to carry fluid, therefore their internal diameter is a critical dimension in determining how much fluid they can carry. This critical dimension is often referred to as the nominal bore, commonly abbreviated as NB. Obviously, for pipes containing pressurized fluids the wall thickness, and by implication the pipe’s strength, is important – too thin and the pipe could rupture.
For all steel pipes with the same NB (nominal bore), the outside diameter remains relatively constant. Therefore any variation in piping schedule i.e. wall thickness, affects only the inside diameter. As the pipe schedule number increases, the wall thickness increases, and the actual bore is reduced. For a given schedule, the outside diameter (OD) increases with nominal pipe size (NPS) while the wall thickness stays constant or increases. Using equations and rules in ASME B31.3 Process Piping, it can be shown that pressure rating decreases with increasing NPS and constant schedule.
Pipe Schedule For Stainless Steel Pipe
Stainless steel offers superior corrosion resistance to carbon steel allowing thinner stainless steel pipe wall thickness to be used. ASME introduced different schedule numbers for stainless steel pipe and fittings. Under ASME B36.19 four new pipe schedules with an “S” suffix were introduced for stainless steel pipe. These stainless steel pipe schedules are: 5S, 10S, 40S and 80S.
Stainless Steel Pipe Weight Chart, KG Per Meter
| Nominal Pipe Size (inches) | Outside Diameter | Schedule | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 5S | 10S | 40S | 80S | |||||||
| (mm) | (inches) | Wall Thickness and Weight | ||||||||
| mm (in) | kg/m | mm (in) | kg/m | mm (in) | kg/m | mm (in) | kg/m | |||
| 1/8 | 10.3 | 0.405 | – | – | 1.25 (0.049) | 0.28 | 1.73 (0.068) | 0.37 | 2.42 (0.095) | 0.47 |
| 1/4 | 13.7 | 0.540 | – | – | 1.66 (0.065) | 0.49 | 2.24 (0.088) | 0.63 | 3.03 (0.119) | 0.80 |
| 3/8 | 17.2 | 0.675 | – | – | 1.66 (0.065) | 0.63 | 2.32 (0.091) | 0.85 | 3.20 (0.126) | 1.10 |
| 1/2 | 21.3 | 0.840 | 1.65 (0.065) | 0.81 | 2.11 (0.083) | 1.00 | 2.77 (0.109) | 1.27 | 3.74 (0.147) | 1.62 |
| 3/4 | 26.7 | 1.050 | 1.65 (0.065) | 1.02 | 2.11 (0.083) | 1.28 | 2.87 (0.113) | 1.68 | 3.92 (0.154) | 2.20 |
| 1 | 33.4 | 1.315 | 1.65 (0.065) | 1.30 | 2.77 (0.109) | 2.09 | 3.38 (0.133) | 2.50 | 4.55 (0.179) | 3.24 |
| 1 1/4 | 42.2 | 1.660 | 1.65 (0.065) | 1.66 | 2.77 (0.109) | 2.69 | 3.56 (0.140) | 3.39 | 4.86 (0.191) | 4.47 |
| 1 1/2 | 48.3 | 1.900 | 1.65 (0.065) | 1.91 | 2.77 (0.109) | 3.11 | 3.69 (0.145) | 4.06 | 5.08 (0.200) | 5.41 |
| 2 | 60.3 | 2.375 | 1.65 (0.065) | 2.40 | 2.77 (0.109) | 3.93 | 3.92 (0.154) | 5.45 | 5.54 (0.218) | 7.49 |
| 2 1/2 | 73.0 | 2.875 | 2.11 (0.083) | 3.69 | 3.05 (0.120) | 5.26 | 5.16 (0.203) | 8.64 | 7.01 (0.276) | 11.4 |
| 3 | 88.9 | 3.500 | 2.11 (0.083) | 4.52 | 3.05 (0.120) | 6.46 | 5.49 (0.216) | 11.3 | 7.62 (0.300) | 15.3 |
| 3 1/2 | 101.6 | 4.000 | 2.11 (0.083) | 5.18 | 3.05 (0.120) | 7.41 | 5.74 (0.226) | 13.6 | 8.08 (0.318) | 18.6 |
| 4 | 114.3 | 4.500 | 2.11 (0.083) | 5.84 | 3.05 (0.120) | 8.37 | 6.02 (0.237) | 16.1 | 8.56 (0.337) | 22.3 |
| 5 | 141.3 | 5.563 | 2.77 (0.109) | 9.46 | 3.41 (0.134) | 11.6 | 6.56 (0.258) | 21.8 | 9.53 (0.375) | 31.0 |
| 6 | 168.3 | 6.625 | 2.77 (0.109) | 11.3 | 3.41 (0.134) | 13.9 | 7.12 (0.280) | 28.3 | 10.98 (0.432) | 42.6 |
| 8 | 219.1 | 8.625 | 2.77 (0.109) | 14.8 | 3.76 (0.148) | 20.0 | 8.18 (0.322) | 42.5 | 12.70 (0.500) | 64.6 |
| 10 | 273.1 | 10.750 | 3.41 (0.134) | 22.7 | 4.20 (0.165) | 27.8 | 9.28 (0.365) | 60.4 | 12.70 (0.500) | 81.5 |
| 12 | 323.9 | 12.750 | 3.97 (0.156) | 31.3 | 4.58 (0.180) | 36.1 | 9.53 (0.375) | 73.9 | 12.70 (0.500) | 97.4 |
Dimensions, wall thickness and weights of stainless steel pipes according to ASME B36.19 Stainless Steel Pipe.