Friction Loss Velocity Table (Schedule 80 pipe)

For steam system to work properly, it is important to maintain reasonable velocities of liquid passing through piping. Pipe velocities are a function of gallons per minute and pipe diameter. Pipe diameters are selected to achieve a velocity of 5-10 feet per second.

Guidelines for using tables:

1. Select value of pump flow (GPM) that is equal to or greater than the pump flow of your application.
2. Velocity is a function of the cross-sectional flow area. Therefore it is constant for a given flow rate and independent of pipe length.
3. Values may vary slightly from other published data due to rounding.
4. Schedule refers to strength of pipe. Wall thickness of pipe varies based on dimensions of pipe as defined in ASME standard 36.10.

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Nominal Size 0.5" 0.75" 1" 1.25" 1.5" 2" 2.5" 3" 4" 5" 6" Nominal Size Pipe OD 0.840 1.050 1.315 1.660 1.900 2.375 2.875 3.500 4.500 5.563 6.625 Pipe OD Pipe ID 0.546 0.742 0.957 1.278 1.500 1.939 2.323 2.900 3.826 4.813 5.761 Pipe ID Wall thickness 0.147 0.154 0.179 0.191 0.200 0.218 0.276 0.300 0.337 0.375 0.432 Wall thickness Q V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction V Friction Q Flow Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Velocity Loss Flow GPM FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI FPS PSI GPM 1 1.37 1.71 0.74 0.39 0.45 0.11 0.25 0.03 0.18 0.01                         1 2 2.74 6.18 1.48 1.39 0.89 0.40 0.50 0.10 0.36 0.05 0.22 0.01                     2 3 4.11 13.10 2.22 2.95 1.34 0.85 0.75 0.21 0.54 0.10 0.33 0.03                     3 4 5.47 22.33 2.96 5.02 1.78 1.45 1.00 0.36 0.73 0.16 0.43 0.05 0.30 0.02                 4 5 6.84 33.75 3.71 7.59 2.23 2.20 1.25 0.54 0.91 0.25 0.54 0.07 0.38 0.03                 5 6 8.21 47.31 4.45 10.63 2.67 3.08 1.50 0.75 1.09 0.35 0.65 0.10 0.45 0.04 0.29 0.01             6 7 9.58 62.94 5.19 14.15 3.12 4.10 1.75 1.00 1.27 0.46 0.76 0.13 0.53 0.05 0.34 0.02             7 8 10.95 80.59 5.93 18.12 3.56 5.25 2.00 1.29 1.45 0.59 0.87 0.17 0.60 0.07 0.39 0.02             8 9 12.32 100.24 6.67 22.53 4.01 6.53 2.25 1.60 1.63 0.73 0.98 0.21 0.68 0.09 0.44 0.03             9 10 13.69 121.84 7.41 27.39 4.45 7.94 2.50 1.94 1.81 0.89 1.09 0.26 0.76 0.11 0.49 0.04             10 11 15.05 145.36 8.15 32.68 4.90 9.47 2.75 2.32 1.99 1.06 1.19 0.30 0.83 0.13 0.53 0.04             11 12 16.42 170.78 8.89 38.39 5.35 11.13 3.00 2.72 2.18 1.25 1.30 0.36 0.91 0.15 0.58 0.05             12 13 17.79 198.07 9.63 44.52 5.79 12.91 3.25 3.16 2.36 1.45 1.41 0.42 0.98 0.17 0.63 0.06 0.36 0.02         13 14 19.16 227.20 10.37 51.08 6.24 14.81 3.50 3.62 2.54 1.66 1.52 0.48 1.06 0.20 0.68 0.07 0.39 0.02         14 15     11.12 58.04 6.68 16.83 3.75 4.12 2.72 1.89 1.63 0.54 1.13 0.22 0.73 0.08 0.42 0.02         15 16     11.86 65.40 7.13 18.96 4.00 4.64 2.90 2.13 1.74 0.61 1.21 0.25 0.78 0.09 0.45 0.02         16 17     12.60 73.18 7.57 21.21 4.25 5.19 3.08 2.38 1.84 0.68 1.29 0.28 0.82 0.10 0.47 0.03         17 18     13.34 81.35 8.02 23.58 4.50 5.77 3.26 2.65 1.95 0.76 1.36 0.32 0.87 0.11 0.50 0.03         18 19     14.08 89.91 8.46 26.07 4.75 6.38 3.45 2.93 2.06 0.84 1.44 0.35 0.92 0.12 0.53 0.03         19 20     14.82 98.88 8.91 28.67 5.00 7.02 3.63 3.22 2.17 0.92 1.51 0.38 0.97 0.13 0.56 0.03         20 22     16.30 117.96 9.80 34.20 5.50 8.37 3.99 3.84 2.39 1.10 1.66 0.46 1.07 0.16 0.61 0.04 0.39 0.01   0.01 22 24     17.79 138.59 10.69 40.18 6.00 9.83 4.35 4.51 2.60 1.29 1.81 0.54 1.16 0.18 0.67 0.05 0.42 0.02   0.01 24 26         11.58 46.60 6.49 11.41 4.71 5.23 2.82 1.50 1.97 0.62 1.26 0.21 0.72 0.05 0.46 0.02   0.01 26 28         12.47 53.45 6.99 13.08 5.08 6.00 3.04 1.72 2.12 0.71 1.36 0.24 0.78 0.06 0.49 0.02   0.01 28 30         13.36 60.74 7.49 14.87 5.44 6.82 3.26 1.96 2.27 0.81 1.46 0.28 0.84 0.07 0.53 0.02 0.37 0.01 30 35         15.59 80.81 8.74 19.78 6.35 9.07 3.80 2.60 2.65 1.08 1.70 0.37 0.98 0.10 0.62 0.03 0.43 0.01 35 40         17.82 103.48 9.99 25.33 7.25 11.62 4.34 3.33 3.02 1.38 1.94 0.47 1.11 0.12 0.70 0.04 0.49 0.02 40 45         20.05 128.71 11.24 31.50 8.16 14.45 4.88 4.14 3.40 1.72 2.18 0.58 1.25 0.15 0.79 0.05 0.55 0.02 45 50         22.27 156.44 12.49 38.29 9.07 17.56 5.43 5.04 3.78 2.09 2.43 0.71 1.39 0.18 0.88 0.06 0.61 0.03 50 55             13.74 45.68 9.97 20.95 5.97 6.01 4.16 2.49 2.67 0.85 1.53 0.22 0.97 0.07 0.68 0.03 55 60             14.99 53.67 10.88 24.62 6.51 7.06 4.54 2.93 2.91 1.00 1.67 0.26 1.06 0.08 0.74 0.04 60 65             16.24 62.24 11.79 28.55 7.05 8.19 4.91 3.40 3.15 1.15 1.81 0.30 1.14 0.10 0.80 0.04 65 70             17.49 71.40 12.69 32.75 7.60 9.39 5.29 3.90 3.40 1.32 1.95 0.34 1.23 0.11 0.86 0.05 70 75             18.74 81.13 13.60 37.22 8.14 10.67 5.67 4.43 3.64 1.51 2.09 0.39 1.32 0.13 0.92 0.05 75 80             19.98 91.43 14.51 41.94 8.68 12.03 6.05 4.99 3.88 1.70 2.23 0.44 1.41 0.14 0.98 0.06 80 85             21.23 102.30 15.41 46.92 9.22 13.46 6.43 5.59 4.12 1.90 2.37 0.49 1.50 0.16 1.04 0.07 85 90             22.48 113.72 16.32 52.16 9.77 14.96 6.80 6.21 4.37 2.11 2.51 0.55 1.59 0.18 1.11 0.07 90 95                 17.23 57.66 10.31 16.53 7.18 6.86 4.61 2.33 2.65 0.61 1.67 0.20 1.17 0.08 95 100                 18.13 63.40 10.85 18.18 7.56 7.55 4.85 2.56 2.79 0.67 1.76 0.22 1.23 0.09 100 110                 19.95 75.64 11.94 21.69 8.32 9.00 5.34 3.06 3.07 0.79 1.94 0.26 1.35 0.11 110 120                 21.76 88.87 13.02 25.48 9.07 10.58 5.82 3.59 3.34 0.93 2.11 0.31 1.48 0.13 120 130                 23.57 103.07 14.11 29.56 9.83 12.27 6.31 4.17 3.62 1.08 2.29 0.35 1.60 0.15 130 140                     15.19 33.90 10.58 14.07 6.79 4.78 3.90 1.24 2.47 0.41 1.72 0.17 140 150                     16.28 38.52 11.34 15.99 7.28 5.43 4.18 1.41 2.64 0.46 1.84 0.19 150 160                     17.36 43.42 12.10 18.02 7.76 6.12 4.46 1.59 2.82 0.52 1.97 0.22 160 170                     18.45 48.57 12.85 20.16 8.25 6.85 4.74 1.78 2.99 0.58 2.09 0.24 170 180                     19.53 54.00 13.61 22.41 8.73 7.62 5.02 1.98 3.17 0.65 2.21 0.27 180 190                         14.37 24.78 9.22 8.42 5.30 2.19 3.35 0.72 2.34 0.30 190 200                         15.12 27.24 9.70 9.26 5.57 2.40 3.52 0.79 2.46 0.33 200 225                         17.01 33.89 10.92 11.51 6.27 2.99 3.96 0.98 2.77 0.41 225 250                         18.90 41.19 12.13 13.99 6.97 3.63 4.40 1.19 3.07 0.50 250 275                         20.79 49.14 13.34 16.69 7.66 4.33 4.84 1.42 3.38 0.59 275 300                         22.68 57.73 14.55 19.61 8.36 5.09 5.28 1.67 3.69 0.70 300 325                             15.77 22.75 9.06 5.91 5.72 1.93 4.00 0.81 325 350                             16.98 26.09 9.76 6.78 6.16 2.22 4.30 0.92 350 375                             18.19 29.65 10.45 7.70 6.60 2.52 4.61 1.05 375 400                             19.41 33.42 11.15 8.68 7.05 2.84 4.92 1.18 400 425                             20.62 37.39 11.85 9.71 7.49 3.18 5.22 1.32 425 450                             21.83 41.56 12.54 10.79 7.93 3.53 5.53 1.47 450 475                             23.04 45.94 13.24 11.93 8.37 3.90 5.84 1.63 475 500                             24.26 50.52 13.94 13.12 8.81 4.29 6.15 1.79 500 550                                 15.33 15.65 9.69 5.12 6.76 2.14 550 600                                 16.72 18.39 10.57 6.02 7.38 2.51 600   Shaded Area represents Velocities over 5 FPS. Use with caution.     OD = Outside Diameter;  ID = Inside Diameter; FPS = Feet Per Second;  GPM = Gallons Per Minute C = Smoothness (roughness) coefficient used in Hazen William's Equation     SDR = Standard Dimension Ratio     Velocity FPS calculated using formula: Friction Losses (PSI) calculated using Hazen William's formula:       These values are calculated using above formula. Values may vary from other published data due to rounding. Values should be used with caution on large systems. Ramesh Kumar, Cal Poly, Pomona.
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