It belongs to the positive displacement pump, relying on the interference fit between the rotor and the fixed stator that does eccentric motion to form a seal cavity that is not connected with each other, and through the rotation of the rotor inside the stator, the sealing cavity moves axially from the inlet end of the pump to the outlet end, so that the medium in the sealing cavity realizes the process of continuous transportation.
The fit between the stator and the rotor is usually a small interference fit, but in the actual selection, not only the influence of the medium temperature, but also the influence of the medium viscosity and the medium on the swelling of the stator rubber should be considered, so it is necessary to compensate for the change of interference caused by the temperature of the medium, viscosity and rubber swelling by reducing the diameter of the rotor.
The structure and characteristics of the progressing cavity pump determine that it is most suitable for conveying a variety of complex media containing solid particles, viscous, corrosive, shear-sensitive, containing fibers and gases, and various harsh working conditions of different temperatures.

The main characteristics of progressing cavity pumps
• High pump efficiency, volumetric efficiency up to 95%, mechanical efficiency up to 65% to 85%, energy saving and consumption reduction;
• No pulsation, no shear, no extrusion, the physical properties of the medium will not be destroyed;
• The rotational speed is proportional to the flow rate, which can be used as a metering pump, and the metering accuracy reaches ±1%;
• The pump has low vibration and low noise during operation, which can realize uninterrupted and continuous transportation of media;
• Suitable for conveying media at various temperatures, from -20°C to +180°C;
• Suitable for conveying all kinds of media with high solid content, with a solid content of up to 45%;
• Suitable for conveying a variety of media with different viscosities, viscosity up to 1,000,000cp;
It is suitable for conveying media containing various fibrous materials, weeds and gases;
• Suitable for conveying polymer chain media with high shear sensitivity or susceptibility to centrifugal force;
• Suitable for conveying multiphase mixtures containing gases, solids and liquids at the same time;
• It has a certain self-priming ability, and the height of the water medium can reach 3-5 meters;
• Simple structure, easy maintenance, no special tools are required to carry out pump maintenance.

Progressing cavity pump application industry:
 Environmental protection
 Conveying slurry or dewatered sludge, the maximum solid content can reach 45%;
Metering and conveying of additives (PCM, PAM, lime milk, etc.) in sewage treatment;
Biogas
 Convey mixtures such as manure straw to the biogas tank, and export the gas slurry or biogas residue after fermentation; transportation of leachate from food waste;
 Petroleum and petrochemical
 Downhole screw pumping pump is commonly used for sand, water and CO2 or H2S crude oil extraction; The multi-phase mixed screw pump can realize the long-distance transportation of crude oil containing sand, gas and water from the oil well storage tank to the joint station. oilfield for the transportation of polymer solutions;
 Fine chemical industry
 Widely used in fine chemical industry processes, for conveying slurry, hydrochloric acid solution, butyraldehyde, etc.;
Emulsion explosives
 Transportation of aqueous matrix, oil matrix and mixed matrix such as ammonium nitrate solution in the production of emulsion explosives; Emulsion explosives application industry in the emulsion explosives vehicle supporting conveying pumps;
 Coal-water slurry
 Conveying of highly abrasive coal-water slurry in coal-water slurry production; Loading, unloading and conveying of coal-water slurry between storage tanks and transport vehicles; high-pressure feeding pump for coal-water slurry boiler;
Mining Engineering
 During mining and beneficiation, the transportation of solid-containing media such as slurry and mortar; delivery of various additives; conveyance of sewage containing solid particles;
 Paper industry
 The single-screw metering pump can realize the accurate injection of various papermaking additives, such as flow aids, brighteners, dispersants, etc., as well as cured starch, rubber and PVA for bonding and coating;
 Food, medicine and cosmetics industries
 In pharmaceutical plants, progressing cavity pumps of hygienic design are used to transport a wide range of raw materials;
 Single-screw pumps can also be seen everywhere in other industries, especially the transportation of syrup, broken apples, tomatoes, distiller's grains, starch, shampoo, emulsion, puree mother liquor, etc.;