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Water piping flow rates

Bigugh! Member Posts: 2
The wide open rule of the thumb is no water hammer and laminar flow. for most piping that is limited at 5 feet per second water flow rate. Calculate the volume of water in a foot of the pipe you want to use. convert it to gallons, Now use that and 5 feet times 6o seconds for one minute then times 60 for the hour. answer is in gph. 3/4 Cu pipe is close at 4 gpm (240 gph)


  • R. Swatton
    R. Swatton Member Posts: 86
    Flow rates

    Anybody know where I can get a formula for the flow rate of copper tubing at diferent preasures in GPM.
    I think I should know this.

    Rich Swatton
  • hr
    hr Member Posts: 6,106
    The PHCC

    had this nice calculator wheel for this puropse. It was based on the National Bureau of Standards 66 & 79. I'll bet this is available online somewhere, now a days. It gave various GPM at both 4 FPS and 8 FPS velocities.

    3/4 copper flowing 11.6 GPM, 7.7 FPS with a whooping 18 psi loss per 100 feet of pipe

    At 3.3 FPS, 5 GPM with 3.9 psi pressure loss per 100 feet of pipe.

    hot rod

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  • Carl PE
    Carl PE Member Posts: 203

    The B&G System Sizer.
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