In many branches of industry bulk materials are conveyed, stored and unloaded. Some of these materials have difficult and varying flow properties. Therefore, the right design and consideration of the silos or hoppers is paramount in the choice of discharge equipment.
Major parameters for the design of discharge systems are bulk density, moisture content, proportionate particle size ranges, temperature, angle of repose and wall friction angle as well as information about the proportion of dust in the material, the abrasiveness and corrosivity.