Abstract: A spiral conveyor comprising a support frame mounted on a base, a plurality of arcuate conveyor sections interconnected to form a helical conveyor having at least one entrance and one discharge, each of said conveyor sections having a plurality of self-driven conveyor rollers, each of said rollers being activated to rotate in clockwise or counterclockwise direction at a selectable speed, sensor means positioned on selected conveyor sections for detecting the presence of a load in such section, and control logic means for operating said rollers in either an upward or a downward direction.