Flow of fluid through a pipe is resisted by viscous shear stresses within the fluid and the turbulence that occurs along the internal pipe wall, which is dependent on the roughness of the pipe material.

 

This resistance is termed pipe friction and is usually measured in feet or metres head of the fluid, which is why it is also refered to as the head loss due to pipe friction.In the calculator below we have the four main off grid pumps we work with, React Pump, Aquatec 4000, Aquatec 6000 and the High-Lifter, and have estimated their flow rates at close to open flow so as to allow for a conservitive estimate of the line losses incurred.