Screw pump, also known as "spiral pump", "Archimedes spiral pump". A pump that USES the rotation of spiral blades to raise water in an axial spiral. By the shaft, spiral blade, shell composition. When pumping, place the pump diagonally in the water, so that the inclination Angle of the main shaft of the pump is smaller than that of the spiral blade, and the lower end of the spiral blade contacts with water. When the prime mover drives the spiral pump shaft to rotate through the speed change device, the water enters the blade, rises along the spiral flow path, until the outflow. Simple structure, easy to manufacture, large flow, small head loss, high efficiency, easy to repair and maintenance, but low head, low speed, need to set up gear change. It is widely used in irrigation, drainage, and lifting of sewage, sludge and other occasions.