It is produced in accordance with the in-canal installation for the purpose of fine sieving of waste water. One of the two sets of gratings in the step grating is fixed and the other is movable. Particles that come with the flow; It is carried up to the discharge point by moving the movable grate set upwards step by step by being held on the screen surface. Since the screening process continues during the upward transport of the particles, the accumulated particles form a filter structure on the screen surface, allowing finer particles to be retained.
