Badger Meter K-Factor Scaler - Manual (Page 13)

Example 2
Known values are:
Full Scale Flow Rate = 85 gpm
Full Scale Output Frequency = 650 Hz
650 Hz × 60 sec = 39,000 pulses per min
K factor
39,000 pulses per min
85 gpm
458.82 pulses per gallon = =
The calculation is a little more complex if velocity is used because you first must convert the velocity into a volumetric flow
rate to be able to compute a K factor
To convert a velocity into a volumetric flow, the velocity measurement and an accurate measurement of the inside diameter
of the pipe must be known Also needed is the fact that one US gallon of liquid is equal to 231 cubic inches
Example 3
Known values are:
Velocity
= 4 3 ft/sec
Inside Diameter of Pipe = 3 068 in
Find the area of the pipe cross section
2
 
 
 
3.068
2
Area = πr 2
Area = π = π x 2.35 = 7.39 in 2
Find the volume in one foot of travel
88.71in 2
7.39 in 2 x 12 in. (1 ft)
ft
=
What portion of a gallon does one foot of travel represent?
= 0.384 gallons
88.71 in 3
231 in 3
So for every foot of fluid travel 0 384 gallons will pass
What is the flow rate in gpm at 4 3 ft/sec?
0 384 gallons × 4 3 fps × 60 sec (1 min) = 99 1 gpm
User Manual
Page 13 November 2013