Pipe Pressure Drop
Pipe Pressure Drop (Schedule 40 Steel Pipe)
The tables in this section provide the air pressure drop in pounds per square inch for a 100 foot length of Schedule 40 Steel Pipe. For lengths other than 100 feet, the pressure drop is proportional to the ratio of difference in lengths.
Example:
For 50 feet of pipe, the pressure drop will be approximately one-half the value given in the table.
For 300 feet of pipe, the pressure drop will be approximately three times the value given in the table.
1/8" Schedule 40 Pipe - .269 actual I.D. |
||||||||
Free Air(SCFM) |
Line Pressure (PSIG) |
|||||||
|
40 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
|
|
1 |
0.757 |
0.64 |
0.554 |
0.489 |
0.437 |
0.395 |
0.361 |
0.332 |
|
2 |
2.747 |
2.323 |
2.011 |
1.774 |
1.587 |
1.435 |
1.31 |
1.205 |
|
3 |
6.416 |
5.425 |
4.697 |
4.144 |
3.706 |
3.352 |
3.06 |
2.815 |
|
4 |
10.128 |
8.564 |
7.414 |
6.541 |
5.85 |
5.291 |
4.83 |
4.444 |
|
5 |
15.622 |
13.209 |
11.436 |
10.089 |
9.023 |
8.162 |
7.45 |
6.854 |
|
6 |
22.227 |
18.794 |
16.271 |
14.354 |
12.839 |
11.612 |
10.6 |
9.752 |
|
8 |
39.002 |
32.978 |
28.551 |
25.188 |
22.528 |
20.377 |
18.6 |
17.112 |
1/4" Schedule 40 Pipe - .364 actual I.D. |
||||||||
Free Air(SCFM) |
Line Pressure (PSIG) |
|||||||
|
40 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
|
|
1 |
0.174 |
0.147 |
0.127 |
0.112 |
0.101 |
0.091 |
0.083 |
0.076 |
|
2 |
0.598 |
0.505 |
0.437 |
0.386 |
0.345 |
0.312 |
0.285 |
0.262 |
|
3 |
1.269 |
1.073 |
0.929 |
0.819 |
0.733 |
0.663 |
0.605 |
0.557 |
|
4 |
2.181 |
1.844 |
1.596 |
1.408 |
1.26 |
1.139 |
1.04 |
0.957 |
|
5 |
3.313 |
2.801 |
2.425 |
2.14 |
1.914 |
1.731 |
1.58 |
1.454 |
|
6 |
4.676 |
3.954 |
3.423 |
3.02 |
2.701 |
2.443 |
2.23 |
2.052 |
|
8 |
8.157 |
6.897 |
5.971 |
5.268 |
4.712 |
4.262 |
3.89 |
3.579 |
|
10 |
12.497 |
10.567 |
9.149 |
8.071 |
7.219 |
6.529 |
5.96 |
5.483 |
|
15 |
27.26 |
23.049 |
19.955 |
17.604 |
15.746 |
14.242 |
13 |
11.96 |
|
20 |
47.809 |
40.424 |
34.998 |
30.876 |
27.615 |
24.978 |
22.8 |
20.976 |
3/8" Schedule 40 Pipe - .493 actual I.D. |
||||||||
Free Air(SCFM) |
Line Pressure (PSIG) |
|||||||
|
40 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
|
|
1 |
0.038 |
0.032 |
0.028 |
0.024 |
0.022 |
0.02 |
0.018 |
0.017 |
|
2 |
0.134 |
0.113 |
0.098 |
0.087 |
0.078 |
0.07 |
0.064 |
0.059 |
|
3 |
0.279 |
0.236 |
0.204 |
0.18 |
0.161 |
0.146 |
0.133 |
0.122 |
|
4 |
0.474 |
0.401 |
0.347 |
0.306 |
0.274 |
0.248 |
0.226 |
0.208 |
|
5 |
0.719 |
0.608 |
0.527 |
0.464 |
0.415 |
0.376 |
0.343 |
0.316 |
|
6 |
0.856 |
0.723 |
0.626 |
0.553 |
0.494 |
0.447 |
0.408 |
0.375 |
|
8 |
1.778 |
1.504 |
1.302 |
1.148 |
1.027 |
0.929 |
0.848 |
0.78 |
|
10 |
2.642 |
2.234 |
1.934 |
1.706 |
1.526 |
1.38 |
1.26 |
1.159 |
|
15 |
4.676 |
3.954 |
3.423 |
3.02 |
2.701 |
2.443 |
2.23 |
2.052 |
|
20 |
9.981 |
8.439 |
7.307 |
6.446 |
5.765 |
5.215 |
4.76 |
4.379 |
|
23 |
13.231 |
11.188 |
9.686 |
8.545 |
7.643 |
6.913 |
6.31 |
5.805 |
|
25 |
15.391 |
13.014 |
11.267 |
9.94 |
8.89 |
8.041 |
7.34 |
6.753 |
|
30 |
22.017 |
18.617 |
16.118 |
14.219 |
12.718 |
11.503 |
10.5 |
9.66 |
|
35 |
29.776 |
25.177 |
21.797 |
19.23 |
17.199 |
15.556 |
14.2 |
13.064 |
|
40 |
38.583 |
32.623 |
28.244 |
24.917 |
22.286 |
20.157 |
18.4 |
16.928 |
|
45 |
48.438 |
40.956 |
35.459 |
31.282 |
27.979 |
25.306 |
23.1 |
21.252 |
1/2" Schedule 40 Pipe - .622 actual I.D. |
||||||||
Free Air(SCFM) |
Line Pressure (PSIG) |
|||||||
|
40 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
|
|
3 |
0.088 |
0.074 |
0.064 |
0.057 |
0.051 |
0.046 |
0.042 |
0.039 |
|
4 |
0.149 |
0.126 |
0.109 |
0.096 |
0.086 |
0.078 |
0.071 |
0.065 |
|
5 |
0.222 |
0.188 |
0.163 |
0.144 |
0.128 |
0.116 |
0.106 |
0.098 |
|
6 |
0.31 |
0.262 |
0.227 |
0.2 |
0.179 |
0.162 |
0.148 |
0.136 |
|
8 |
0.535 |
0.452 |
0.391 |
0.345 |
0.309 |
0.279 |
0.255 |
0.235 |
|
10 |
0.746 |
0.631 |
0.546 |
0.482 |
0.431 |
0.39 |
0.356 |
0.328 |
|
15 |
1.749 |
1.479 |
1.28 |
1.129 |
1.01 |
0.914 |
0.834 |
0.767 |
|
20 |
2.999 |
2.535 |
2.195 |
1.936 |
1.732 |
1.567 |
1.43 |
1.316 |
|
25 |
4.634 |
3.918 |
3.392 |
2.993 |
2.677 |
2.421 |
2.21 |
2.033 |
|
30 |
6.605 |
5.585 |
4.835 |
4.266 |
3.815 |
3.451 |
3.15 |
2.898 |
|
35 |
8.912 |
7.535 |
6.524 |
5.755 |
5.148 |
4.656 |
4.25 |
3.91 |
|
40 |
11.512 |
9.734 |
8.427 |
7.435 |
6.649 |
6.014 |
5.49 |
5.051 |
|
45 |
14.469 |
12.234 |
10.592 |
9.344 |
8.357 |
7.559 |
6.9 |
6.348 |
|
50 |
17.803 |
15.053 |
13.032 |
11.497 |
10.283 |
9.301 |
8.49 |
7.811 |
|
60 |
25.582 |
21.631 |
18.727 |
16.521 |
14.777 |
13.365 |
12.2 |
11.224 |
|
70 |
34.599 |
29.255 |
25.328 |
22.344 |
19.985 |
18.076 |
16.5 |
15.18 |
|
80 |
44.873 |
37.942 |
32.849 |
28.98 |
25.92 |
23.444 |
21.4 |
19.688 |
|
90 |
56.616 |
47.871 |
41.445 |
36.563 |
32.702 |
29.579 |
27 |
24.84 |
3/4" Schedule 40 Pipe - .824 actual I.D. |
||||||||
Free Air(SCFM) |
Line Pressure (PSIG) |
|||||||
|
40 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
|
|
5 |
0.057 |
0.048 |
0.041 |
0.037 |
0.033 |
0.03 |
0.027 |
0.025 |
|
6 |
0.078 |
0.066 |
0.057 |
0.05 |
0.045 |
0.041 |
0.037 |
0.034 |
|
8 |
0.13 |
0.11 |
0.095 |
0.084 |
0.075 |
0.068 |
0.062 |
0.057 |
|
10 |
0.197 |
0.167 |
0.144 |
0.127 |
0.114 |
0.103 |
0.094 |
0.086 |
|
15 |
0.421 |
0.356 |
0.309 |
0.272 |
0.243 |
0.22 |
0.201 |
0.185 |
|
20 |
0.723 |
0.612 |
0.53 |
0.467 |
0.418 |
0.378 |
0.345 |
0.317 |
|
25 |
1.103 |
0.933 |
0.807 |
0.712 |
0.637 |
0.576 |
0.526 |
0.484 |
|
30 |
1.568 |
1.326 |
1.148 |
1.013 |
0.906 |
0.819 |
0.748 |
0.688 |
|
35 |
2.097 |
1.773 |
1.535 |
1.354 |
1.211 |
1.096 |
1 |
0.92 |
|
40 |
2.726 |
2.305 |
1.996 |
1.76 |
1.575 |
1.424 |
1.3 |
1.196 |
|
45 |
3.397 |
2.872 |
2.487 |
2.194 |
1.962 |
1.775 |
1.62 |
1.49 |
|
50 |
4.173 |
3.528 |
3.055 |
2.695 |
2.41 |
2.18 |
1.99 |
1.831 |
|
60 |
5.976 |
5.053 |
4.375 |
3.859 |
3.452 |
3.122 |
2.85 |
2.622 |
|
70 |
8.031 |
6.791 |
5.879 |
5.187 |
4.639 |
4.196 |
3.83 |
3.524 |
|
80 |
10.38 |
8.776 |
7.598 |
6.703 |
5.995 |
5.423 |
4.95 |
4.554 |
|
90 |
13.106 |
11.081 |
9.594 |
8.464 |
7.57 |
6.847 |
6.25 |
5.75 |
|
100 |
16.125 |
13.634 |
11.804 |
10.414 |
9.314 |
8.424 |
7.69 |
7.075 |
|
125 |
24.953 |
21.099 |
18.267 |
16.115 |
14.413 |
13.037 |
11.9 |
10.948 |
|
150 |
35.647 |
30.141 |
26.095 |
23.021 |
20.59 |
18.624 |
17 |
15.64 |
|
175 |
48.438 |
40.956 |
35.459 |
31.282 |
27.979 |
25.306 |
23.1 |
21.252 |
1" Schedule 40 Pipe - 1.049 actual I.D. |
||||||||
Free Air(SCFM) |
Line Pressure (PSIG) |
|||||||
|
40 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
|
|
50 |
1.212 |
1.025 |
0.887 |
0.783 |
0.7 |
0.633 |
0.578 |
0.532 |
|
60 |
1.717 |
1.452 |
1.257 |
1.109 |
0.992 |
0.897 |
0.819 |
0.753 |
|
70 |
2.307 |
1.95 |
1.689 |
1.49 |
1.332 |
1.205 |
1.1 |
1.012 |
|
80 |
2.999 |
2.535 |
2.195 |
1.936 |
1.732 |
1.567 |
1.43 |
1.316 |
|
90 |
3.774 |
3.191 |
2.763 |
2.438 |
2.18 |
1.972 |
1.8 |
1.656 |
|
100 |
4.634 |
3.918 |
3.392 |
2.993 |
2.677 |
2.421 |
2.21 |
2.033 |
|
125 |
7.108 |
6.01 |
5.204 |
4.591 |
4.106 |
3.714 |
3.39 |
3.119 |
|
150 |
10.212 |
8.635 |
7.475 |
6.595 |
5.899 |
5.335 |
4.87 |
4.48 |
|
175 |
13.839 |
11.702 |
10.131 |
8.938 |
7.994 |
7.23 |
6.6 |
6.072 |
|
200 |
17.907 |
15.141 |
13.109 |
11.565 |
10.344 |
9.356 |
8.54 |
7.857 |
|
225 |
22.646 |
19.148 |
16.578 |
14.625 |
13.081 |
11.832 |
10.8 |
9.936 |
|
250 |
27.889 |
23.581 |
20.416 |
18.011 |
16.109 |
14.57 |
13.3 |
12.236 |
|
275 |
33.55 |
28.368 |
24.56 |
21.667 |
19.379 |
17.528 |
16 |
14.72 |
|
300 |
39.841 |
33.687 |
29.165 |
25.73 |
23.013 |
20.815 |
19 |
17.48 |
|
325 |
46.761 |
39.538 |
34.231 |
30.198 |
27.01 |
24.43 |
22.3 |
20.516 |
|
350 |
54.1 |
45.743 |
39.603 |
34.938 |
31.249 |
28.264 |
25.8 |
23.736 |





























































































