To get maximum starch recovery, while keeping any fiber in the final product to an absolute minimum, it is necessary to wash the free starch from the fiber during processing. The pressure arc screens are arranged for countercurrent washing of the fiber, with the starch reporting to the undersize. The extremely fine separations are possible only with highly polished wedge wire screen surfaces under certain pressure. This kind of screen is called pressure arc screen which is used in various part of corn starch processing line.