Natural gas pipe selection

[dallas]

Could someone please tell me if this is correct:

Appliance BTUh = 72000
Natural gas BTU/CF= 1025

72000/1025= 70.2 CF/hr

at 8 psi inlet pressure

Pipe size of 1 inch is fine correct.

 

[Goorah]

Dallas:

You need to factor in the length of run of your pipe and all the fitting (elbows, tees, valving, etc) to see if the resultant P-drop results in satisfactory supply pressure to whatever it is you are delivering the gas. Many appliances "expecct" a minimum supply gas pressure.

Consult the IFGC (International Fuel Gas Code) for quick and easy line size selections.

 

[fredb]

Hello

Flow of high pressure gas in standard wall pipe is usually accompanied by a considerable pressure drop and decrease of the density along the entire line. The flow is expressed by the equation: Q = d to the 8/3 power x the sq root of (P1 squared minus P2 squared), all divided by the square root of (Sa x L), then multiply the product of the division x 33.95

Q = Flow of free gas at 60 degrees F (cubic feet/min.)
d = Inside dia. of the pipe in inches
P1 = Initial pressure (psi absolute)
P2 = Final pressure (psi absolute)
Sa = Specific gravity of the gas (air = 1)
L = Effective length of the pipeline in feet