Fig. 6.6.6. Individual drive from flanged motor coupled to gear box (c) Portable Roller Conveyor It is a short (up to 7 m) section of roller conveyor mounted on legs and at times with wheels. These may be shifted from one place to another and adjusted in height or inclination for loading and unloading of trucks. The portable roller conveyor may be idle or driven. Drive is often through an endless belt described above. 6.6.3 Aspects of Roller Conveyor Design (a) Unpowered Roller Conveyors The major design calculations involved are to determine the force required to overcome the resistance to motion of the loads and the angle of inclination required for gravity conveyor. a