CRITICAL CARRYING VELOCITY C065
When you are pumping a slurry you must be aware of the velocity of the liquid and solids mixture to prevent the solids from settling out on the bottom of a horizontal pipe.
Since the solids are kept in suspension by turbulence it is important that the velocity be high enough to prevent settling but not so high that excessive friction occurs in the piping.
The frictional loss in a pipe increases by about 90% of the square of the flow velocity so it is desirable to keep the flow velocity as low as possible.
A carrying velocity in the range of 4-7 feet per second (1.2 to 2.3 m/s) is both practical and economical.
Be aware that pipe abrasion can occur at velocities above 10 feet per second (3 m/s).