Friction loss for PVC class 160 pipe

Nominal pipe size
Actual inside diameter

 0.5
0.720 		1
1.195 		2
2.193 		3
3.230 		4
4.154
Velocity in feet per second (fps) and friction loss in psi per 100 feet1
flow,
gpm 		fps1 psi fps2 psi fps1 psi fps1 psi fps1 psi
1 0.8 0.202 0.28 0.02            
2 1.6 0.75 0.57 0.06            
3 2.4 1.56 0.85 0.14            
4 3.2 2.68 1.14 0.232            
5 4.0 4.04 1.42 0.35            
6 4.8 5.76 1.17 0.49            
7 5.6 7.66 1.99 0.66            
8 6.4 9.78 2.28 0.84            
                     
10     2.85 1.27 0.84 0.07        
16     4.57 3.04 1.35 0.16        
20     5.71 4.59 1.69 0.242 0.78 0.04 0.47 0.01
40     11.42 16.59 3.39 0.86 1.58 0.13 0.94 0.04
55         4.66 1.56 2.15 0.242 1.30 0.07
                     
80         6.78 3.12 3.12 0.47 1.89 0.14
100         8.48 4.72 3.91 0.72 2.36 0212
130             5.08 1.17 3.07 0.34
200                 4.72 0.76
225                 5.31 0.95
1 Water velocities limited to 5 feet per second (fps) in pipe selection. Use larger velocities with caution.
2 Pipe flow rates can be compared at similar friction losses (0.21 to 0.24 psi per 100 feet). Note that two times the diameter means four times the flow capability for the same friction loss. Actual pipe diameter should be used for more accurate ratios.

Water velocity and friction loss data for sizing PVC Class 160 pipe for various flow rates.