Flat bottomed steel silos are with large diameter and capacity, which is popular for its easy installation and lower costs. There are many ways for unloading, such as the free-fluidized unloading, multi-spot unloading, the flat bottom sweeping unloading and clean by hands etc... We can also choose the concrete conical bottom to put the automatic-flow unloading into practice. The flat-bottom steel silos can be widely used in grain process and storage lines, some of them can be chosen to be used in oil, feed, flour, starch, brew, and port or grain storage industrial lines.