Abstract: The invention is an improved conveyor apparatus for unloading bulk material from bulk material transportation systems, such as railcars. The conveyor apparatus is provided with a housing that is waterproof to the atmosphere and tight internally against dust leakage from conveyed materials, the housing enclosing a motor-driven continuous chain having segmented Z-shaped flights attached to the chain. Two different materials can be unloaded by the present apparatus, one such material on each side of the segmented flights. The present apparatus is also capable of conveying bulk material at any angle between 0 and 90.degree. from the point of entry of said material into the apparatus, and between 0.degree. and 45.degree. from the point of entry of the materials into the apparatus when the mixing of dissimilar conveyed materials (i.e. contamination) is to be prevented.