basics

Can an air-driven diaphragm pump replace a multistage pump?

September 25, 2025
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Choosing the right pump for your industry is one of the most important engineering decisions and directly impacts efficiency, operating costs, and the service life of the system. Many industrial processes require pumping fluids under high pressure or unusual operating conditions. In such cases, two pump types are typically considered:

The key question is whether air-operated diaphragm pumps can replace multistage pumps in certain applications. To answer this question, it is necessary to first understand the characteristics, advantages, and disadvantages of each pump type and then compare them in different applications.

Repair of a double-acting pneumatic diaphragm pump

Introduction to the pneumatic diaphragm pump

Pneumatic diaphragm pumps are powered by compressed air and do not require an electric motor. These pumps move the fluid through the reciprocating motion of the diaphragm.

Special feature

  • Suitable for transporting all types of liquids: liquid, viscous, corrosive or with solid particles.

  • Self-study.

  • It can dry out without causing damage.

  • Possibility of operation in potentially explosive environments (due to the lack of an electric motor).

  • Simple design and easy maintenance.

End

  • Flow and pressure are limited (typically up to 8–10 bar).

  • Less efficient than centrifugal pumps.

  • A sufficient supply of compressed air is required.

Introduction to multistage pumps

Multistage pumps are typically centrifugal pumps     and use     multiple impellers in series to gradually increase the fluid pressure.

Special feature

  • This creates a very high pressure (depending on the design, this can be several hundred times higher).

  • Continuous fluid supply with high efficiency.

  • Suitable for applications such as boiler feed pumps, pressurized water systems, reverse osmosis systems and the oil and gas industry.

End

  • Increased sensitivity to solid particles and aggressive liquids.

  • Requires careful sealing and lubrication.

  • In some cases, maintenance costs are higher.

Dotik

A practical comparison of air-driven pumps and multistage diaphragm pumps

1. Working pressure

  • Multi-stage:     Can deliver very high pressure (sometimes over 50 bar).

  • Pneumatic diaphragms:     These are typically limited to pressures of 8 to 10 bar.
    👉They are therefore not a replacement for applications where high pressure is critical.

2. Liquid type

  • Multi-stage:     Suitable for clean water or liquids with very few particles.

  • Air-operated diaphragm pumps:   Diaphragm pumps can transport corrosive, viscous and abrasive liquids or solid particles and
    👉are the ideal choice in   the food   , paint, pharmaceutical and chemical industries.

3. Compressed air is required.

  • Multi-stage:     Driven by electric or  diesel engines  .

  • Pneumatic diaphragm pump:     Requires a compressed air system with sufficient flow and pressure.
    👉In systems without compressed air, the use of diaphragm pumps is limited.

4. Energy efficiency

  • Multi-stage:     High efficiency and optimal energy consumption.

  • Pneumatic diaphragm pumps: lower    efficiency    and higher compressed air consumption.
    👉Multistage pumps are more economical for long-term continuous operation.

5. Maintenance and safety

  • Multi-stage:     requires more frequent maintenance and is more sensitive to cavitation     and particles     .

  • Pneumatic diaphragms:     easier    to    maintain, suitable for operation in potentially explosive environments, and better protected against sudden failures.

Can it be replaced?

Non-replaceable  applications:

  1. Boiler feed pumps:     These require very high pressure, which diaphragm pumps cannot deliver.

  2. Reverse osmosis (RO) system:     Requires high and stable pressure; a multi-stage system is the best option.

  3. Transporting water under high pressure and over long distances:     Only multi-stage water transport can meet this demand.

Alternative applications     :

  1. Pumping corrosive chemical liquids or liquids containing solid particles:     Diaphragm pumps are more suitable due to their corrosion resistance and ability to move particles.

  2. Food and pharmaceutical industries:     Handling sensitive liquids requiring hygienic design (FDA or EEHC approval).

  3. Temporary or emergency use:     When a portable, quickly installed pump is needed.

  4. Explosive environments (ATEX zones):     where no electric motor is used.

Let’s summarize the advantages and disadvantages in the table.

Special feature Pneumatic diaphragm pumps multi-stage pump
Working pressure Up to 8-10 times up to a hundred times
Dubai Medium to low Medium to high
Liquid type A corrosive, sticky substance containing solid particles. Clean water or liquid with low particle content
Efficiency Reduced higher
energy compressed air Electric motor or diesel engine
Save Easier and cheaper More professional, more expensive
Protection Suitable for potentially explosive environments Electrical protection required.
Main areas of application Chemical, food and pharmaceutical industries as well as transport of hazardous liquids Boilers, pressurized water systems, reverse osmosis systems and heavy industry

Finally

Pneumatic diaphragm pumps and multistage pumps occupy a special position in various industries, but cannot completely replace each other.

  • Choose a multi-stage pump   if you     need high pressure     , good energy efficiency and a constant supply of clean water.

  • Air-operated diaphragm pumps are ideal     for applications where the fluid is corrosive, viscous, sensitive, or contains solids.

In other words, the choice between two pumps depends on     the type of fluid, the required pressure, the ambient conditions, and energy and maintenance costs  . In many sensitive processes, the two pump types can complement each other rather than completely replace each other.