When to use?
The progressive cavity pump is a positive displacement positive displacement pump, which is used in many fields, especially suitable for conveying suspensions containing gas and solid particles or short fibers, as well as media with very high viscosity and and sensitive liquid that cannot be sheared, squeezed or stirred. Of course, various corrosive materials can also be transported.
When the viscosity or thickness of liquid is higher than water, and centrifugal pump or gear pump is not applicable, please use progressive cavity pump.
In general, when the viscosity of liquid increases, the mechanical efficiency and volumetric efficiency of centrifugal pump will be greatly reduced, which means that the flow rate decreases and the power consumption increases.
The progressive cavity pump is the opposite of the centrifugal pump. When the viscosity increases, the power decreases and the flow rate increases, the mechanical efficiency and volumetric efficiency will increase.
In addition, since the progressive cavity pump is a positive displacement pump, which transports fluid by advancing the volume cavity, it will have approximately the same flow rate regardless of the viscosity of the liquid.
If you have a pumping application that requires a constant flow, but the viscosity of the liquid is variable and will change, then the PC pump is an ideal choice.
When there are abrasive solids in the liquid, gear pumps or vane pumps will simply wear out. This also happens to most centrifugal pumps, and they may become clogged.
Most other types of positive displacement pumps cannot pump solids well or for very long periods of time due to their tight tolerances and all-metal design.
Because the progressive cavity pump transports fluid along the axial direction by the cooperation of stator and rotor, they do not travel outside the housing along a high-speed cycle like other pump designs, and the abrasive particles are parallel to the pumping surface and travel at a low speed, it will not wear them in large areas.
In addition, the rubber stator of progressive cavity pump has “bounce” phenomenon. If the particles contact with the stator, the stator has a certain degree of movement flexibility and will not wear, which makes its service life longer than the metal parts of other types of pumps in abrasive applications. The progressive cavity pump can also reduce the wear and tear by reducing the rotating speed.
When the application requires varying flow rates, the progressive cavity pump is the ideal pump.
Because the progressive cavity pump is a positive displacement pump, the volume cavity is fixed and its flow is proportional to the speed. Therefore, we usually control the flow by adjusting the speed of the pump.
Modern pump speed controllers such as variable frequency drives (VFD) stepless speed reducers are very suitable for use with progressive cavity pumps to change pump speed and flow control.
The classic centrifugal pump is usually used in boiler feed water application. Due to the change of flow demand, the customer used PC pump.
At the same time, compared with plunger pumps, diaphragm pumps and gear pumps, the progressive cavity pump has a precise flow rate per revolution, which can be used for medicament filling and metering.
When sensitive liquids that cannot be sheared, squeezed or agitated, or the structure of the medium cannot be destroyed, the progressive cavity pump is the most ideal application time.
A good example is when transporting colloidal liquids such as certain cosmetics, etc., you must pay attention to the matching of the pump speed and the characteristics of the transported medium.
Because most colloidal liquids become viscous or even solid when they are at rest, they become more fluid and semi-fluid after being stirred. This phenomenon is the thixotropic phenomenon of colloidal liquids.
Therefore, an appropriate speed must be selected, and care must be taken not to damage the structure of the medium by thixotropy.
Another good example of when to use a progressive cavity pump is when the suction conditions for pumping applications are not ideal.
Compared with the piston pump, the progressive pump has self-priming capacity, and the suction height can reach 8.5 m water column.
Compared with centrifugal pumps, progressive cavity pumps require a much lower net positive suction head (NPSH) because of their lower internal pump speed.
When the suction pressure is as low as 28 inches of mercury (Hg), the progressive cavity pump can pump, but the centrifugal pump cannot.
When the pressure is greater than the centrifugal pump application, we usually consider the progressive cavity pump.
The maximum pressure is 48 bar.
Where will the progressive cavity pump be used?
Transportation of raw sludge, mud, dewatered sludge, electrolyte, additives (PCM, PAM, lime milk, etc.), waste gas treatment, sewage and gypsum
Transportation of latex, lime slurry, cellulose, additives (flow aids, brighteners, dispersants), cured starch, titanium dioxide, alum, water glass, soda ash, rubber, glue, PVA
Convey dough, palm oil, olive oil, ice cream, jam, honey, meat sauce, sausage, potato residue, caramel, soft candy, syrup, mustard, tomato sauce, distiller’s grains, starch, Laoganma and pet food
Transportation of cream, additives, gel, shampoo, emulsion, mother liquor and ointment.
Convey latex paint, paint, various toners, additives
Transportation of crude oil, lubricant, mineral oil, sludge, tar, water oil emulsion, heavy oil, paraffin, polymer solution
Conveying beer, distiller’s grains, wort, yeast, jam, fruit juice, concentrated drinks, flavors, additives
Transportation of various inorganic acids, alkalis, additives, suspensions, sludge, etc
Transportation of concrete, cement, bentonite, gravel, slurry, mortar, sand, various additives, lime, lime suspension, solid particle sewage
Transportation of liquid fertilizer, pet liquid and its food, biological products, etc
Convey the mixture of manure and straw to the biogas tank, and output the gas-containing biogas slurry or biogas residue after fermentation.
In the modern unmanned assembly workshop, the high precision small metering pump can cooperate with the mechanical arm to complete the gluing process.
Conveying coal water slurry, raw materials for preparing emulsion explosives that are sensitive to shear, desulfurization wastewater, and sludged lead paste.