Head Losses in the Piping
H
V
m/100 m
The friction losses given in the above chart roughly apply to new
cast iron pipes. For new rolled steel or plastic pipes, multiply the
values by approx. 0.8. For old, slightly rusty cast iron pipes,
multiply by approx. 1.25. In pipes with incrustations, friction
losses may rise to 1.7 times the value given in the chart for the
10
60 Hz
Submersible Borehole Pumps
diameter reduced by incrustations. For pipes subject to con-
siderable incrustation, the friction losses can only be deter-
mined experimentally.
Example: Q = 140 m
H
= 3.25 m per 100 m of pipe, v = 2.2 m/sec.
V
3300:103/3-2
3
/h, new DN 150 cast iron pipe.
H
V
ft/100 ft