... , sole pump, etc. When the 2 simultaneous reverse rotating rotors (with 2-4 gears) revolve, it produces suction force at the ... it revolves to position a, only housing I is filled with medium;when it revolves to position b, housing B encloses ... continuously. Welcome to contact us for more information Centrifugal Pump,High Quality Pump,delivery pump,pump for shampoo machine