Progressive cavity pumps – find manufacturers and suppliers

Progressing cavity pumps are versatile, robust and powerful positive displacement pumps that really come into their own when it comes to the gentle, continuous pumping of viscous, abrasive or solids-containing media.

Thanks to their low-pulsation pumping characteristics, self-priming properties and high controllability, they are indispensable in many sectors such as waste water technology, the food industry and chemicals.

Below you will find information on how progressing cavity pumps work, their design and special variants, their typical areas of application and their advantages and disadvantages:

How progressing cavity pumps work:

It is a rotating positive displacement pump that works by the principle of a rotating screw (rotor) in a fixed rubber or elastomer housing (stator).

1. The rotor rotates eccentrically within the stator.
2. Continuously sealed cavities are created which move forward along the pump axis.
3. The medium is conveyed gently, with low pulsation and continuously from the suction to the discharge side.

Design of progressing cavity pumps:

1. Rotor: A metallic, helical shaft with eccentric rotation (usually made of stainless steel).
2. Stator: Rubberized or elastomer housing, inside in mirror-image screw shape.
3. Drive: Electric motor with gearbox that generates the eccentric movement of the rotor.
4. Cardan shaft: Connects the drive to the rotor and balances the eccentric movement.
5. Sealing system: Prevents the pumped medium from escaping, e.g. mechanical seal.

Variants and special versions of progressing cavity pumps:

1. Hygienic design: CIP/SIP-capable, e.g. in the pharmaceutical and food industries.
2. Dosing pumps: Precise, small-volume delivery.
3. Mobile pumping stations: For construction sites, emergency or tanker emptying.
4. High-pressure versions: Multi-stage systems for long pipelines.

Typical areas of application for progressive cavity pumps:

1.Industry:
Chemical industry: Dosing of polymer slurries, chemicals, oils.
Food industry: Conveying dough, yoghurt, fruit juice with fruit pieces.
Paper and pulp industry: transportation of pulp suspensions.
Construction industry: Cement mortar, plaster, screed.

2. Environmental and waste water technology:
Sewage treatment plants: sludge transportation, especially primary, secondary and digested sludge.
Biogas plants: liquid manure, substrate mixtures, fermenter feeding.
Drinking water treatment: flocculants, milk of lime.

3. Oil and gas industry:
Pumping heavy crude oil, sludges with sand content, drilling muds.

Advantages of progressive cavity pumps:

• Self-priming, even with gas-laden media.
• Uniform volume flow, virtually pulsation-free.
• Gentle pumping of sensitive media.
• Pumping of highly viscous or solids-laden liquids.
• Flow rate proportional to speed, therefore easily adjustable.
• Conveying direction reversible.

Disadvantages of progressing cavity pumps:

• The stator wears out with abrasive media.
• Sensitive to dry running → dry running protection required.
• Larger design compared to other pump types.
• Relatively high purchase and maintenance costs for special designs.

Despite the higher purchase and maintenance costs compared to other pump types, their use is worthwhile where process reliability, media diversity and gentle pumping are paramount. Wear caused by abrasive substances and the risk of dry running are critical and should be minimized by suitable monitoring systems.
The progressive cavity pump is the first choice for demanding pumping tasks where other pumps reach their limits.

Here you will find an overview of the most important criteria that you should pay attention to when purchasing progressive cavity pumps:

When purchasing progressive cavity pumps, it is crucial to consider not only the technical specifications but also economic, operational and maintenance-related aspects.

• The central basis for selection is precise knowledge of the pumping medium. The following parameters in particular need to be clarified:
• Viscosity of the medium? Low to extremely high.
• Solid content and particle size, e.g. sand, fibers, organic substances.
• Abrasiveness and corrosiveness as well as the chemical composition, pH value.
• Temperature* of the medium in continuous operation
• Sensitivity to shear forces, e.g. with emulsions or biological substrates.
• Gas content in the medium.
• These properties influence the selection of rotor/stator materials and the design of the pump.
• The required flow rate in m³/h or l/min as well as the system back pressure caused by the pressure head, pipe losses and valves determine the pump size and design:
• Progressing cavity pumps are speed-dependent → delivery rate proportional to speed
• Multi-stage designs are necessary for higher differential pressures, e.g. > 6 bar.
• The pump runs more gently at low speeds → less wear.
• The right choice of materials for the rotor, stator, seals and housing is crucial for durability and process compatibility:
• Rotors: Mostly stainless steel, coated if necessary (chrome, carbide)
• Stators: Elastomers (NBR, EPDM, FKM, etc.), depending on temperature, chemicals and abrasion.
• Seals: Mechanical seals, stuffing boxes or special shaft sealing systems - depending on operating conditions.
• The design can vary depending on the installation location, space conditions and degree of automation:
• Horizontal or vertical design.
• Compact or modular for simplified maintenance.
• For mobile use, either mounted on a frame or chassis.
• CIP/SIP-capable for hygienic applications, e.g. in food or pharmaceuticals.
• The flange and connection dimensions must be compatible with the piping system.
• Which drive technology and which type of control is appropriate for the application:
• Choice between direct drive, geared motor or frequency-controlled motor.
• For variable speed applications: Use of frequency inverters.
• Explosion-proof design (ATEX) for flammable media or potentially explosive environments.
• Possibility of integration into PLC or a higher-level control system.
• Professional procurers pay attention to a low-maintenance design and fast availability of spare parts:
• The following equipment is relevant to protect the pump and system:
• Dry-running protection e.g. a thermal sensor in the stator.
• Pressure sensors for monitoring blockages or leaks.
• Temperature and current monitoring of the motor.
• Leakage monitoring in the event of sealing problems.
• Depending on the industry and region, certain standards must be met:
• Hygiene approvals such as EHEDG, FDA, 3-A for food and pharmaceuticals.
• ATEX certification for potentially explosive atmospheres.
• CE conformity and machinery directive.
• Complete technical documentation, drawings, maintenance instructions, spare parts lists.
• In addition to the acquisition costs, the life cycle costs (total cost of ownership) are decisive.
• Consider the initial costs of the pump, but also the total costs over the service life (maintenance, operation, energy).
• Carry out a cost-benefit analysis to find the most economical solution that meets your requirements.
• A more expensive pump may be more cost-effective in the long run if it is more durable and easier to maintain.

Professional purchasing of progressive cavity pumps requires much more than just a comparison of price and flow rate. A thorough analysis of the operating conditions, media-dependent material selection, sensible additional equipment as well as ease of maintenance and operational safety are essential. This is the only way to ensure a reliable, durable and economical solution for the respective application.

Progressing cavity pumps can be purchased from various suppliers. You will find comprehensive information on manufacturers and suppliers of Progressing Cavity Pumps around the world on Exportpages.