A screw conveyor or auger conveyor is a device that uses a rotating helical screw blade, called a “flighting”, usually within a tube or trough, to transfer semi-solid materials, powder, granular and small lumpy materials such as slurry waste, wood chips, aggregates, cereal grains, animal feed, boiler ash, meat and bone meal, municipal solid waste, and many others. The rotating part of the conveyor is sometimes called simply an auger.

The auger conveyor is a very economical method to elevate and convey semi-solid materials by place the screw conveyor horizontally or at a slight incline. As the angle of inclination increases, the capacity of the auger rapidly decreases.