The biggest characteristic of progressive cavity pump is that it is especially suitable for conveying sensitive liquids which cannot be sheared, squeezed or stirred, that is, non-Newtonian liquids which will show thixotropic properties when subjected to shearing. It is not only suitable for transporting medium with low viscosity such as water, but also especially suitable for transporting suspension containing solid particles or short fibers and medium with very high viscosity.

Since the stator and the rotor are in an interference fit, they cannot be idling or dry running; The contact surface of the stator and the rotor usually needs a layer of fluid film to maintain lubrication.
When the fluid with high viscosity and poor fluidity is input, we need to pay attention to whether it can flow into the pump fast enough. If it cannot, it will easily cause the dry grinding and volumetric efficiency of the pump to change. So we need to pay attention to the speed of the fluid being conveyed and its viscosity.
For fluids with lower water content, the transport distance is shorter and higher pressure is required.
In order to ensure the life of the progressive cavity pump, we usually control the speed to a low level so that a large flow will not be generated. If you need to increase the flow, usually add a variable frequency drive (VFD) or stepless speed reducer. Speed and flow are often proportional. But the maximum flow rate of the progressive cavity pump in our factory can reach: 300m³/h;
The slip rate of low-viscosity fluid between the stator and the rotor is very high, which is likely to cause the efficiency of the pump to decrease.
The possible high starting torque may require the driver (motor) to be larger than otherwise required. Operating horsepower may be only half of the required starting horsepower.
Because the stator is rubber, large temperature fluctuation will lead to slight expansion, which means that the efficiency, flow rate and pressure will be different.

No, it’s not.
The progressive cavity pump is a positive displacement pump. It has only one screw rotor, which has slight interference fit with the rubber stator. Screw pumps also need at least two screw rotors to cooperate, and usually there are three or five screw rotors to cooperate. The name is also named after the number of screw rotors. For example, a pump with two screw rotors is called a twin screw pump.
Comparison of the media conveyed by different types of screw pumps:
Twin screw pump can transport lubricating, non-lubricating, corrosive and medium containing certain magazines, even used for oil, steam and liquid mixed transportation. Commonly used for conveying various oils, water, emulsion, paste, asphalt and chemical media, etc.
Three screw pump usually delivers lubricating oil, fuel oil, hydraulic oil, sealing oil-grade coolant, etc.
Five-screw pump is suitable for low-pressure and high-flow conditions, conveying lubricating medium, and it is more sensitive to impurities in the medium than three screw pump.
Screw pumps are not made of rubber like progressive cavity pumps, but almost all of them are made of metal. Performance: Screw pump can deliver larger flow and pressure.

No, it can’t.

Due to the slight interference fit between the stator and the rotor of the progressive cavity pump, it is not allowed to run dry. Once the dry running of the pump is not stopped in time, the stator will burn out immediately. Therefore, it is necessary to fill the pump cavity with the medium, and the medium in the system cannot be interrupted.

Special situation: When installing the pump, if you don’t know whether the motor is in the forward or reverse direction, you can run the pump 1-2 times in dry mode.

Yes, it is.

It was invented by French engineer MoiNeau, so it is called Mono Pump. It has many nicknames. Sometimes we will call it helical rotor pump, eccentric screw pump, PC Pump or PCM Pump, Crank Rod Pump and Snake Pump. In China, it is also called single screw pump and thick slurry pump. No matter how many nicknames it has, it belongs to positive displacement pump.

In 1930, when aviation pioneer René Moineau was designing compressors for early jet engines, he discovered that this principle could work efficiently for pumping fluids. So he cooperated with Robert Bienaime of Gevelot Group to establish PCM Pompes in 1932 and developed the world’s first known progressive cavity pump.

Founder of the PCM company in 1932, René Moineau is the inventor of the Progressing cavity pump, also known as Moineau pump Mono pump or PCM Pump.

When the viscosity or thickness of the liquid is higher than that of water, which is not suitable for centrifugal pump delivery, use progressive cavity pump.

When flow rate changes. Generally centrifugal pumps cannot achieve flow rate changes, while screw pumps can be achieved by adjusting the speed.

When the suction conditions of the pumping applications are not ideal and when the suction pressure is lower than 28 inches of mercury (Hg), the progressive cavity pump can pump, but the centrifugal pump cannot.

When transporting sensitive liquids that cannot be sheared, squeezed or agitated, the speed of the centrifugal pump is too high, which will easily damage the fluid structure.

When the liquid contains solid particles, centrifugal pumps or other positive displacement pumps are easy to wear or block. At this time, because the stator and rotor of the progressive cavity pump has a wear resistance design, it will be more suitable for this application.

The main working parts of progressive cavity pump are stator and rotor. Because of the special geometric shape of stator and rotor, when assembled together, several separate sealing cavities will be formed. When the motor drives the rotor to move, the medium in each sealing cavity will be continuously and uniformly transported from the suction end to the extrusion end with constant volume.

It needs to be selected according to the physical and chemical properties of the conveyed medium in the current application;

Key technical factors:

1. Pump displacement

2. Pressure or conveying distance (including horizontal and vertical distance and number of elbows)

3. Media physical characteristics:

    Viscosity >>>>> (considering its fluidity)
    Temperature >>>>> (whether high and low temperature resistance is required)
    Abrasivity >>>>> (with or without solid particles)

4. Chemical properties of medium

    Corrosivity >>>>> (pH value)

5. Flow change >>>>> (consider using variable frequency motor)

Other factors:

1. Client’s choice and budget

2. On-site installation space

3. On-site environmental requirements >>>>> (using electricity or diesel power)

4. Installation method

Confirm the above information, and finally consider the material selection and processing technology of the pump body and its spare parts.

Finally, our factory will give you a reasonable and satisfactory design plan.

Progressive cavity pumps have self-priming performance and good suction performance, and the self-priming height is generally 2-5 meters (taking water as the test); When transporting sludge or medium with high viscosity, self-priming installation is generally not recommended, but natural inflow is recommended.

Usually we call the pump body as the pump cavity, that is, a closed space can be formed when the medium contacts the pump body or other parts.