Design of Screw Conveyor Size of Screw Conveyor Screw Aug 10, 2011 Capacity of Screw Conveyor: 01screw conveyor capacity calculationscrew conveyor manufacturersscrew conveyor shaft screw. The capacity of a screw conveyor depends on the screw diameter, screw pitch, speed of the screw and the loading efficiency of the cross sectional area of the screw.