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How to calc C factor in DI pipe with multiple corp taps?

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HBData

Civil/Environmental
Oct 24, 2017
2
I'm calculating C Factor of existing pipe in an operating water distribution system. I'm trying account my K losses, (fittings, other factors). I have an 8" inch Ductile Iron pipe and have about 17-1"inch corps tapped into the main throughout. The threads on these corps protrude in the DI pipe approximately an inch to 1/2 inch. How would one account for the resistance coefficient (K) for the 1-inch corp taps in my 8"DI pipe? If the inside liner looks like porcupine from the tapped service line connections this could be throwing my data off?
 
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How long is this pipe? What "C" value are you using for the ductile pipe alone? What is the "C" value for the liner?
 
I have various stretches or runs of pipe that I'm attempting to calculate the actual C factor for. The general Hazen Williams values table with ranges based on age-- I have that.

I'm attempting calculate my pipe based on the actual conditions of my system utilizing Hazen Williams and Darcy Weisbach formulas to calculate the actual c factor of my pipe. My runs are 400 to 1500 LF. I'm using a series of 3 hydrants, 2 of the hydrants have pressure data loggers G1, G2 and the third hydrant "Q" is the being flowed from the steamer port and I'm collecting my GPM with an Ultra Sonic flow meter. I'm now factoring in elevation, joints, valves and bends into my equation as "losses".

I'm trying to determine some sort of resistance coefficient for the 1 inch taps that protrude in the pipe liner.



 
Very small compared to all the other losses
but if you really want to see what it is, I would calculate the losses of an orifice plate with an equal projected area and use that in the Darcy Weisbach equation to get an estimate

Hydrae
 
never heard of this being done, these are truly "minor" losses compared to 1500 LF of bell and spigot waterline. not sure what the end game of this exercise is
 
Most engineers would ignore the minor headloss from corp. taps.
 
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