The screw pump is composed of a pump body and one or more screws. The principle of twin-screw pump is very similar to gear pump. The customization of energy-saving rotor pump is to pump liquid with the help of screw teeth. Screw pump is divided into single screw pump, twin-screw pump and three screw pump according to the number of screws, in which the twin-screw pump is divided into closed type and non closed type. There are many structural types of rotary piston pump, among which the most common are cam pump and roots vacuum pump. Cam pump is a kind of multi-functional double positive displacement pump, which is one of the most excellent liquid conveying mechanical equipment in the world. The price of rubber rotor pump is to select two rotors for fitness exercise at the same time. The rotor is driven by a pair of external synchronous transmission gears. The rotor is driven by the rotating shaft to carry out reverse rotation at the same time. The middle of the rotor and the middle of the rotor and the pump shell touch each other, It is suitable for the transportation of food, pharmaceutical, corrosive and low viscosity materials. Flexible impeller pump belongs to the capacity rotor pump.