Slurry pipeline system inlet pipe diameter should be bigger than the slurry pump inlet and outlet pipe diameter not less than the pump outlet. So the inlet and outlet pipe specifications should be calculated base on optimum flow rate by rigorous economic comparison.
The importance of slurry pump inlet pipe is more importance than the outlet, the inlet pipe must have a good seal, and as far as possible to shorten the length (but the slurry pump inlet anterior preferably four times the diameter length of straight pipe), and to reduce valves and elbows, etc. the number of piping components, if any, elbow, elbow bending radius should be as large as possible, in order not let the air run into inlet pipeline, usually make the water gathered inside the air inlet pipe slightly on the ramp to couple with the pump inlet valve.
In addition, the inlet pipe should have a filter. All piping connected to the slurry pump should be independent and with secure support to mitigate vibration of piping and prevent piping weight on the slurry pump.