Screw conveyors are popular devices for conveying farm products. Thousands of portable units have been used to move or elevate grains into and out of storage bins. As one aspect of increased farmstead mechanization, many auger conveyors are being installed as integral parts of continuous-flow systems. They are very effective conveying devices for free-flowing or relatively free-flowing bulk solids, giving good throughput control and providing environmentally clean solutions to process handling problems because of their simple structure, high efficiency, low cost and maintenance requirement.