Abstract: The slit spiral tube for self-cleaning pressure filters in which the spiral element is mounted on supports, by maintaining the spiral circumferential slit wherein, in the spiral circumferential slit (s) there is a fixed working spiral moving back and forth. The slot self-cleaning pressure filter for dewatering liquid media consisting of a cylindrical casing in which there is a medium inflow, an effluent outflow and a sludge overflow and slit spiral tubes placed centrally, axially one in another, out of which each tube has a spiral element fixed on supports by maintaining the spiral circumferential slit, wherein, in the spiral circumferential slit (s) of both the external slit spiral tube and the internal slit spiral tube a working spiral moving back and forth is mounted, whereas, between the slit spiral tubes and a motor-driven spiral rotatable scraper is mounted.