Where:

H=

height (the elevation difference)

SG =

specific gravity before rising to the higher power.

2,31 =

conversion constant (1 psi = 2.3 1 feet of head of water at 70 degrees F.)

Example:

Height (800 to 850 feet) 50 feet (uphill elevation difference).

Specific Gravity (58 degrees API converts to) 0.7467

pipeline.

Example: Pressure gage readings; 225 and 195 psi, the difference between the two = 30 psi.

(1) To correct the pressure take the pressure difference from the gages which equals 30 psi and

subtract the pressure determined from the elevation which is; 16.

(2) With a gage pressure of 30 psi subtract 16 psi this gives an answer of 14 psi. The figure of 14 is

used in the Hazen Williams equation for "p".

30 psi - 16 psi = 14 psi.

Pressure gage reading: 175 psi and 165 psi = 10 psi.

Elevation: 745 and (downstream) 742 = 3 feet

SG.:

0.7467

Example: 10 psi - 1 psi = 9 psi used in the formula this has corrected for the gage reading and not for the actual

friction and pressure loss.

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