As in any engineering design exercise, the design and selection of conveyors and handling equipment for a particular process or system involves the consideration of a number of alternative solutions. The overall or global problem requires comparisons to be made between different types of equipment and modes of transport with economic considerations playing a major role in the final decision making. When different modes of conveying and transportation are compared, such as belts, buckets, pipelines, rail and road, the variations in costs may differ by several orders of magnitude. Even when one mode of conveying, such as belt conveying, is examined for a particular installation, within the range of possible combinations of conveyor size, speed and geometrical layout, there can be considerable variations in the overall costs. For the reasons stated it is particularly important that the conditions for optimum performance of particular types of conveyors and handling equipment be established. Furthermore, in view of the heavy dependence by industry on bulk materials handling operations, any increases in efficiency, even if only small, can lead to substantial cost savings.