Hi everyone, I am in the process of putting together a water feature and am having trouble selecting the correct pump for the job. The pump will be required to pump water to a vertical distance of approx 7.4 meters. A submersible pump would be best. The pipe coming up from the pump is 12mm in diameter and has four 90 elbows and one globe valve. From my calculations based on the head loss due to the elbows, friction and the valve I require a pump with a maximum head of around 35.4 feet. A side question, if the output on my pump is 1 inch lets say and I put in a pipe reducer directly after the pump which reduces the diameter of the pipe from 1 inch to ½ inch how will that effect the flow rate/pressure and the max head achievable by the pump?
Any help would be great!
Best Regards,
Josh
Pump Selection/Head Calculations
Re: Pump Selection/Head Calculations
Centrifugal pumps does not have constant flow rate. It changes with respect to resistance it has to manage. So if you reduce the pipe diameter, flow rate will be smaller for the same pump. To know how the flow will change you have to know pump characteristics, ie. head-flow curve. When you have that curve, you should draw your pipe line curve - I can help you with it - and on cross between two curves you will get your actual flow rate.
Pipe flow calculations - since 2000