Irrigation
Pressure Loss in Pipes from Friction
Calculate the pressure loss caused by friction in a section of irrigation pipeline.
Calculation
- select the pipe material in use
- the flow rate of the water in (US gallons per minute)
- inside diameter of the pipe (inches)
- length of the pipe (feet)
- Fittings and Valves Equivalent Length
Results
- friction loss per foot of pipe psi/ one foot
- friction loss for the calculated amount of straight pipe psi/feet
- total friction loss straight pipe plus equivalent length of fittings
| PVC and CPVC Pipes - Schedule 40 |
| Nominal Size | Outer Diameter | Inside Diameter |
| 1/8" | 0.405" | .249" |
| 1/4" | 0.540" | .344" |
| 3/8" | 0.675" | .473" |
| 1/2" | 0.840" | 0.622" |
| 3/4" | 1.05" | .825" |
| 1" | 1.315" | 1.049" |
| 1 1/4" | 1.66" | 1.38" |
| 1 1/2" | 1.9" | 1.61" |
| 2" | 2.375" | 2.067" |
| 2 1/2" | .203" | 2.469" |
| 3" | 3.5" | 3.068" |
| 4" | 4.5" | 4.026" |
| 5" | 5.563" | 5.047" |
| 6" | 6.625" | 6.065" |
| 8" | 8.625" | 7.981" |
| 10" | 10.75" | 10.02" |
| 12" | 12.75" | 11.938" |
| 14" | 14" | 13.124" |
| 16" | 16" | 15" |
| 18" | 18" | 16.876" |
| 20" | 20" | 18.814" |
| 24" | 24" | 22.626" |
| PVC and CPVC Pipes - Schedule 80 |
| Nominal Size | Outer Diameter | Inside Diameter |
| 1/8" | 0.405" | 0.195" |
| 1/4" | 0.54" | 0.302" |
| 3/8" | 0.675" | 0.403" |
| 1/2" | 0.84" | 0.546" |
| 3/4" | 1.05" | 0.742" |
| 1" | 1.315" | 0.957" |
| 1 1/4" | 1.660" | 1.278" |
| 1 1/2" | 1.900" | 1.500" |
| 2" | 2.375" | 1.939" |
| 2 1/2" | 2.875" | 2.323 |
| 3" | 3.500" | 2.900" |
| 4" | 4.500" | 3.826" |
| 5" | 5.563" | 4.813" |
| 6" | 6.625" | 5.761" |
| 8" | 8.625" | 7.625" |
| 10" | 10.750" | 9.564" |
| 12" | 12.750" | 11.376" |
| 14" | 14.000" | 12.500" |
| 16" | 16.000" | 14.314" |
| 18" | 18.000" | 16.126" |
| 20" | 20.000" | 17.938" |
| 24" | 24.000" | 21.564" |
| PVC Class 160 IPS Plastic Pipe |
| Nominal Size | Outer Diameter | Inside Diameter |
| 1/2" | 0.840" | 0.696" |
| 3/4" | 1.050" | 0.910" |
| 1" | 1.315" | 1.175" |
| 1-1/4" | 1.660" | 1.512" |
| 1-1/2" | 1.900" | 1.734" |
| 2" | 2.375" | 2.173" |
| 2-1/2" | 2.875" | 2.635" |
| 3" | 3.500" | 3.210" |
| 4" | 4.500" | 4.134" |
| 6" | 6.625" | 6.084" |
| 8" | 8.625" | 7.921" |
| 10" | 10.750" | 9.874" |
| 12" | 12.750" | 11.710" |
| 14" | 14" | 12.860" |
| 16" | 16" | 14.696" |
| 18" | 18" | 16.532" |
| PVC Class 200 IPS Plastic Pipe |
| Nominal Size | Outer Diameter | Inside Diameter |
| 1/2" | 0.840" | 0.696" |
| 3/4" | 1.050" | 0.910" |
| 1" | 1.315" | 1.169" |
| 1-1/4" | 1.660" | 1.482" |
| 1-1/2" | 1.900" | 1.700" |
| 2" | 2.375" | 2.129" |
| 2-1/2" | 2.875" | 2.581" |
| 3" | 3.500" | 3.146" |
| 4" | 4.500" | 4.046' |
| 6" | 6.625" | 5.955" |
| 8" | 8.625" | 7.755" |
| 10" | 10.750" | 9.666" |
| 12" | 12.750" | 11.464" |
| 14" | 14" | 12.588" |
| 16" | 16" | 14.384" |
| 18" | 18" | 15.246" |
| PVC Class 315 IPS Plastic Pipe |
| Nominal Size | Outer Diameter | Inside Diameter |
| 1/2" | 0.840" | 0.696" |
| 3/4" | 1.050" | 0.874" |
| 1" | 1.315" | 1.101" |
| 1-1/4" | 1.660" | 1.394" |
| 1-1/2" | 1.900" | 1.598" |
| 2" | 2.375" | 1.983" |
| 2-1/2" | 2.875" | 2.423" |
| 3" | 3.500" | 2.948" |
| 4" | 4.500" | 3.794" |
| 6" | 6.625" | 5.583" |
Cisterns, Tanks and Rainwater Harvesting
Water Flow Rate Calculators
Water Pressure and Friction Loss
Conversions