Research: Flow rate (GPM) vs Pipe size vs Pressue (PVC)

DISCLAIMER: Remember all of the following are just general guidelines and should not be relied on as a precise source for information.

  

Key points to remember:

• Pressure loss: As fluid flows through a pipe, it experiences pressure loss due to friction. Longer pipes and higher flow rates generally lead to greater pressure loss.
• Noise: High flow velocities can cause noise in pipes. Minimizing noise often involves using larger pipes or reducing flow rates.
• Safety: Exceeding the pressure rating of a pipe can be dangerous. Always consult with a qualified professional if you're unsure about the safe operating pressures for your piping system.
  
  
  

NOMOGRAPH: FLOW RATE vs PIPE SIZE

How to use a Nomograph:

1. You should size your pipe so that your flow velocity stays in the green or yellow range.
2. The green range is safest, most efficient and will produce little to no noise. 
3. Flow velocities in the yellow range may be noisy and have additional back pressure. 
4. Flow velocities in red are not recommended because of the risk of hydraulic shock and pipe/fitting/joint & pump failure.
5. Find your flow in the first column (GPM) and then select the pipe size you want in the second column (pipe, ID in inches.) 
6. Draw a straight line between them all the way to the last column. If the line ends up in the green you are good. If it ends in the yellow or red, increase the pipe size until your line ends in the green (best) or yellow (just okay) area.
   

NOTE: 
These figures are for straight pipe only! The effect of putting direction changes in will compound the back pressure even more and could even result in failure of the system or burning up the pump.
You will never be hurt by going to a bigger pipe and will gain by using less electricity due to a more efficient system which may offset the initial price difference for the larger pipe.

PVC material chemical resistance chart wrt Temperature

References:
https://cdn.flexpvc.com/graphics/head-loss-nomograph-chart.gif
https://flexpvc.com/docs/chemical-ratings.png
https://flexpvc.com/docs/ChemicalRatingsChartForPVCPlastics.pdf
https://flexpvc.com/Reference/FeetOfHeadPressureToPSIChart.pdf
https://flexpvc.com/Reference/PVC-Pipe-Weight-Per-Foot.shtml
https://flexpvc.com/Reference/WaterFlowBasedOnPipeSize.shtml
https://hy-techroofdrains.com/water-flow-through-a-pipe/