Flow, pressure, and pipe diameter?

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SUMMARY

This discussion focuses on the relationship between pipe diameter and flow rate in a water pumping scenario. A 1.25" diameter pipe typically achieves a maximum flow rate of 30-40 gallons per minute (gpm), while a 10" diameter pipe can reach 2500-3000 gpm. The flow rate is not directly proportional to the diameter; doubling the diameter results in a flow rate increase of four times, not double. Additional factors such as inlet and outlet pressure, fittings, elevation change, pipe material, and fluid type must be considered for accurate flow calculations.

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  • Understanding of fluid dynamics principles
  • Knowledge of pipe sizing and flow rate calculations
  • Familiarity with pressure measurements in psi
  • Basic concepts of hydraulic systems and fittings
NEXT STEPS
  • Research the Darcy-Weisbach equation for calculating pressure loss in pipes
  • Learn about the Hazen-Williams equation for estimating flow in water pipes
  • Explore the impact of fittings and valves on flow rate
  • Study the effects of elevation change on fluid flow in piping systems
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Engineers, plumbers, and anyone involved in fluid transport systems will benefit from this discussion, particularly those focused on optimizing water flow in piping networks.

davehans
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If I have water being pumped through two lengths of pipe, both at 50 psi, but one pipe is 1.25" diameter and the other is 10" diameter, approimately how many gpm will be flowing through each pipe? Thanks in advance!
 
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There is not enough information for an answer with absolute volume, but only relative volume rate.
 
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I can tell you that a 1.25" pipe will generally have a maximum practical flow of ~30-40 gpm and a 10 inch pipe will have a maximum practical flow of somewhere in the range of 2500-3000 gpm. However, each of these pipes can have any flow in between 0 and their maximum practical flow (and beyond, in some/many cases).

If you want to know actual flow, you need to provide more information, at least:
-inlet pressure (check)
-outlet pressure
-fittings? (valves, elbows, meters, etc)
-elevation change?
-Pipe material?
-Fluid type? (water? Syrup?)
 
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Thanks guys. Those numbers are close enough for me to have made my point in a discussion... the point being that 10 times the diameter is NOT 10 times the flow... :-) ......especially when we already know that double the diameter is 4x the flow...
 

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