Traveling band screens are typically installed in an intake screening system downstream from the trash rakes or coarse bar screens and upstream of the circulating water pump. Their main function is to remove debris (from 1 mm-10 mm) before the circulating water is distributed to sensitive plant components. When water flows through the panels of the traveling water screen, debris is collected on the mesh panels. As the screen rotates, the debris is carried up to deck level where a pressure spray flushes it from the panels into a debris trough. The clean panels then rotate back into the water, resulting in continuous, uninterrupted screening. Traveling band screens are generally installed with one of three possible flow patterns: external to internal dual-flow, internal to external dual-flow (center-flow), or thru-flow. More