Pressure Ratings of Schedule size MS Seamless Pipes

In the context of pipes, the term “schedule” is used to specify the wall thickness of the pipe, which affects its pressure-bearing capacity and various other mechanical properties. The designation “Schedule Standard” is typically used for carbon steel pipes aka mild steel (MS) pipes and is governed by standards such as ASME B36.10M.

Pipes with different schedules are used in various applications based on the pressure and temperature requirements of the fluid being transported. Thicker-walled pipes are used for higher-pressure applications, while thinner-walled pipes are suitable for lower-pressure applications.

Here are some approximate pressure ratings for Schedule 40 carbon steel pipes according to ASME B36.10M:

Nominal Pipe Size (or) Nominal Bore (NB)	Schedule 40 Pressure Rating (psi)	Schedule 40 Pressure Rating (Bar)
1/8	1380	95.10
1/4	1310	90.31
3/8	1160	79.99
1/2	1030	71.03
3/4	990	68.24
1	840	57.91
1 1/4	840	57.91
1 1/2	860	59.29
2	750	51.71
2 1/2	720	49.62
3	700	48.26
3 1/2	750	51.71
4	730	50.34
5	710	48.98
6	700	48.26
8	660	45.52
10	620	42.75
12	610	42.06
14	550	37.92
16	530	36.55
18	520	35.86
20	500	34.49
24	500	34.49

Following are some approximate pressure ratings for Schedule 80 carbon steel pipes according to ASME B36.10M:

Nominal Pipe Size (or) Nominal Bore (NB)	Schedule 80 Pressure Rating (psi)	Schedule 80 Pressure Rating (Bar)
1/8	2220	153.24
1/4	3140	216.18
3/8	2660	183.31
1/2	2570	177.13
3/4	2590	178.45
1	2140	147.49
1 1/4	2060	142.07
1 1/2	1960	134.97
2	1820	125.51
2 1/2	1770	121.89
3	1710	117.79
3 1/2	1670	115.15
4	1600	110.32
5	1520	104.84
6	1440	99.36
8	1350	93.16
10	1250	86.19
12	1210	83.41
14	1160	79.99
16	1100	75.84
18	1040	71.70
20	990	68.24
24	940	64.78

The full details of ASME B36.10M standard which is for Welded and Seamless Wrought Steel Pipes may be purchased online at the official website https://www.asme.org/. It is a paid document which must be referred to for accurate information.