Table 14.6. Pressure Loss of Water Due to Friction in Types K, L and M Copper Tube (psi per linear foot of tube)
(Part 1: ¼ through 2)

Table 6 is divided into 2 parts:
Part 1: ¼ through 2 | Part 2: 2½ through 12

Flow GPMNominal or standard size, inches
1⁄43⁄81⁄23⁄4111⁄411⁄22
KLMKLMKLMKLMKLMKLMKLMKLM
1 0.138 0.118 N/A 0.036 0.023 0.021 0.010 0.008 0.007 0.002 0.001 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
2 N/A 0.130 0.084 0.075 0.035 0.030 0.024 0.006 0.005 0.004 0.002 0.001 0.003 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
3 N/A 0.275 0.177 0.159 0.074 0.062 0.051 0.014 0.011 0.009 0.003 0.003 0.001 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.000 0.000
4 N/A 0.125 0.106 0.086 0.023 0.018 0.015 0.006 0.005 0.004 0.002 0.002 0.002 0.001 0.001 0.001 0.000 0.000 0.000
5 N/A 0.189 0.161 0.130 0.035 0.027 0.023 0.009 0.007 0.006 0.003 0.003 0.002 0.001 0.001 0.001 0.000 0.000 0.000
10 N/A 0.126 0.098 0.084 0.031 0.027 0.023 0.010 0.010 0.009 0.004 0.004 0.004 0.001 0.001 0.001
15 N/A 0.065 0.057 0.049 0.022 0.020 0.018 0.009 0.009 0.008 0.002 0.002 0.002
20 N/A 0.096 0.084 0.037 0.035 0.031 0.016 0.015 0.014 0.004 0.004 0.004
25 N/A 0.057 0.052 0.047 0.024 0.022 0.021 0.006 0.006 0.005
30 N/A 0.079 0.073 0.066 0.034 0.031 0.029 0.009 0.008 0.008
35 N/A 0.045 0.042 0.039 0.012 0.011 0.010
40 N/A 0.058 0.054 0.050 0.015 0.014 0.013
45 N/A 0.062 0.018 0.017 0.016
50 N/A 0.022 0.021 0.020
60 N/A 0.031 0.029 0.028
70 N/A 0.042 0.039 0.037
80-2000 N/A

NOTES:
1. Fluid velocities in excess of 5-8 feet per second are not recommended.
2. Friction loss values shown are the flow rates that do not exceed a velocity of 8 feet per second.
3. Highlighted and italicized friction loss values indicate flow rates that are between 6 feet and 8 feet per second.
4. Table 14.6 is based on the Hazen-Williams formula:
Hazen-Williams formula
Where:
P=friction loss, psi per linear foot
Q=flow, g.p.m.
d=average I.D., in inches
C=constant, 150