The screw sludge dewaterinng machine belongs to the screw press, it's clog-free and can reduce the sedimentation tank and sludge thickening tank, saving the cost of sewage plant construction. Using screw and the moving rings to clean itself as clog-free structure, and controlled by the PLC automatically, it's a new technology that can replace the traditional filter press like belt press and frame press, the screw speed is very low, so it cost low power and water consumption in contrast to the centrifuge, it is a cutting edge sludge dewatering machine.It concentrates and dehydrates sewage directly in 24 hours continuously and efficiently with self-service operating and greatly reduces the cost of design,construction,operation maintenance and management.