For testing material flow in a realistic, continuous flow process, J&H has set up in our new lab a full screen loop.  A small bucket elevator carries the product material to the top of the lab, and lets the product flow down through a screen feeder and 10 foot screen machine just as it would in a processing plant.  At the discharge, there are ports to test for screening efficiency.  The material then recombines and is mixed in a screw conveyor that brings it back up to the bucket elevator feed chute.