PipeData

Schedule 30 Pipe Dimensions

Wall thickness, bore and plain-end weight for all 27 sizes ASME B36.10M publishes in schedule 30, NPS 1/8 through NPS 36.

Schedule
Schedule 30
Sizes published
27 (NPS 1/8 to NPS 36)
Thinnest wall
0.057 in (1.4 mm) at NPS 1/8
Thickest wall
0.625 in (15.9 mm) at NPS 28
Standard
ASME B36.10M

Where schedule 30 is used

Schedule 30 exists only in the larger sizes and sits between Schedule 20 and Schedule 40. It is used for large-diameter, low-pressure lines where Schedule 20 leaves too little margin.

Pipe wall thickness to scale, Schedule 30Pipe cross-sections drawn to scale at the same outside diameter so the wall thicknesses can be compared. NPS 1/8: 0.057 in wall on 0.405 in OD; NPS 8: 0.277 in wall on 8.625 in OD; NPS 36: 0.625 in wall on 36.000 in ODNPS 1/80.057 in wall on 0.405 in ODNPS 80.277 in wall on 8.625 in ODNPS 360.625 in wall on 36.000 in OD
Schedule 30 in three sizes, each drawn to its own scale. The sections are drawn at the same width so that the wall can be compared with the diameter it belongs to. The wall gets thicker as the size goes up, but it takes up a smaller share of the pipe.

Schedule 30 in every size

Dimensions are given in inches, with the millimetre equivalent beneath in grey.

ASME B36.10M schedule 30 dimensions.
SizeDNOutside diameterWall thicknessInside diameterWeight, emptyWater (US gal/ft)This size
NPS 1/8DN 60.40510.29 mm0.0571.45 mm0.2917.39 mm0.210.32 kg/m0.003all schedules →
NPS 1/4DN 80.54013.72 mm0.0731.85 mm0.39410.01 mm0.360.54 kg/m0.006all schedules →
NPS 3/8DN 100.67517.14 mm0.0731.85 mm0.52913.44 mm0.470.70 kg/m0.011all schedules →
NPS 1/2DN 150.84021.34 mm0.0952.41 mm0.65016.51 mm0.761.13 kg/m0.017all schedules →
NPS 3/4DN 201.05026.67 mm0.0952.41 mm0.86021.84 mm0.971.44 kg/m0.030all schedules →
NPS 1DN 251.31533.40 mm0.1142.90 mm1.08727.61 mm1.462.18 kg/m0.048all schedules →
NPS 1 1/4DN 321.66042.16 mm0.1172.97 mm1.42636.22 mm1.932.87 kg/m0.083all schedules →
NPS 1 1/2DN 401.90048.26 mm0.1253.17 mm1.65041.91 mm2.373.53 kg/m0.111all schedules →
NPS 2DN 502.37560.32 mm0.1253.17 mm2.12553.97 mm3.014.47 kg/m0.184all schedules →
NPS 2 1/2DN 652.87573.02 mm0.1884.78 mm2.49963.47 mm5.408.04 kg/m0.255all schedules →
NPS 3DN 803.50088.90 mm0.1884.78 mm3.12479.35 mm6.669.91 kg/m0.398all schedules →
NPS 3 1/2DN 904.000101.60 mm0.1884.78 mm3.62492.05 mm7.6611.40 kg/m0.536all schedules →
NPS 4DN 1004.500114.30 mm0.1884.78 mm4.124104.75 mm8.6712.90 kg/m0.694all schedules →
NPS 8DN 2008.625219.07 mm0.2777.04 mm8.071205.00 mm24.7236.79 kg/m2.658all schedules →
NPS 10DN 25010.750273.05 mm0.3077.80 mm10.136257.45 mm34.2751.00 kg/m4.192all schedules →
NPS 12DN 30012.750323.85 mm0.3308.38 mm12.090307.09 mm43.8165.20 kg/m5.964all schedules →
NPS 14DN 35014.000355.60 mm0.3759.52 mm13.250336.55 mm54.6281.28 kg/m7.163all schedules →
NPS 16DN 40016.000406.40 mm0.3759.52 mm15.250387.35 mm62.6493.21 kg/m9.489all schedules →
NPS 18DN 45018.000457.20 mm0.43811.13 mm17.124434.95 mm82.23122.37 kg/m11.964all schedules →
NPS 20DN 50020.000508.00 mm0.50012.70 mm19.000482.60 mm104.23155.11 kg/m14.729all schedules →
NPS 22DN 55022.000558.80 mm0.50012.70 mm21.000533.40 mm114.92171.02 kg/m17.993all schedules →
NPS 24DN 60024.000609.60 mm0.56214.27 mm22.876581.05 mm140.81209.55 kg/m21.351all schedules →
NPS 28DN 70028.000711.20 mm0.62515.88 mm26.750679.45 mm182.90272.18 kg/m29.195all schedules →
NPS 30DN 75030.000762.00 mm0.62515.88 mm28.750730.25 mm196.26292.07 kg/m33.724all schedules →
NPS 32DN 80032.000812.80 mm0.62515.88 mm30.750781.05 mm209.62311.95 kg/m38.579all schedules →
NPS 34DN 85034.000863.60 mm0.62515.88 mm32.750831.85 mm222.99331.84 kg/m43.760all schedules →
NPS 36DN 90036.000914.40 mm0.62515.88 mm34.750882.65 mm236.35351.73 kg/m49.268all schedules →

Weight is plain-end carbon steel, w = 10.69 × t × (OD − t) lb/ft.

How the wall changes with size

The wall in schedule 30 is 0.057 in (1.4 mm) at NPS 1/8 and 0.625 in (15.9 mm) at NPS 36. Measured against the pipe it belongs to, that is 14.1% of the outside diameter at the small end and 1.7% at the large end, so the wall does not keep pace with the diameter. The pressure the pipe will hold moves the same way. On the basis used throughout this site (ASME B31.3, S = 20,000 psi, nominal wall, no corrosion allowance) schedule 30 holds about 6,344 psig at NPS 1/8 and about 704 psig at NPS 36. A schedule is therefore chosen size by size, from a calculation, and not once for a whole plant.

From NPS 28 up to NPS 36 the wall is the same in every size, 0.625 in (15.9 mm). Over that range schedule 30 is a fixed thickness and no longer a series that climbs with the size.

In this schedule the wall thickness coincides with STD in NPS 14 through NPS 16 and XS in NPS 20 through NPS 22. Outside those sizes it does not, so never substitute one designation for the other without checking the number.

Guides and comparisons for this page

What a pipe schedule actually isWhy a schedule is a wall series and not a thickness.Pipe wall thickness calculationBarlow and ASME B31.3, corrosion allowance and mill tolerance.Pipe sizing by flow rate and velocityTurn a flow rate into a line size using velocity limits.

Common questions

What sizes is schedule 30 pipe made in?

ASME B36.10M publishes schedule 30 in 27 sizes, from NPS 1/8 through NPS 36. Wall thickness runs from 0.057 in (1.4 mm) at the small end to 0.625 in (15.9 mm) at the large end.

Does schedule 30 mean the same wall thickness in every size?

No. It is a series, not a thickness. The wall is 0.057 in (1.4 mm) at NPS 1/8 and 0.625 in (15.9 mm) at NPS 36, so the thickness always has to be read off the table for the size in hand.

How pipe schedules work →