Air-operated diaphragm pumps – find manufacturers and suppliers

Air-operated diaphragm pumps are  pumps that use compressed air to move flexible diaphragms in order to pump liquids or slurries gently and self-priming.

Thanks to their simple but effective operation, they can pump a wide range of liquids - from aggressive chemicals to sensitive foodstuffs. The purely pneumatic drive ensures high operational reliability, even under difficult conditions.

Below you will find the mode of operation, the variety of media and the typical areas of application of air-operated diaphragm pumps as well as their advantages:

How air-operated diaphragm pumps work:

Components of air-operated diaphragm pumps:

Diaphragm pumps consist of a housing with two pump chambers, two flexible diaphragms, non-return valves (e.g. ball or flap valves) and a centrally controlled air valve. (distributor mechanism).

Sequence of the pumping process of air-operated diaphragm pumps:

1. Compressed air flows into one of the two air chambers behind a diaphragm.
2. The air pressure pushes the diaphragm outwards, causing liquid to be expelled from the opposite pump chamber.
3. The second diaphragm, mechanically connected to the first, moves synchronously and draws new fluid into its chamber.
4. The air valve automatically changes the pressure side so that the movement is reciprocal - creating a continuous flow.
5. The diaphragms act like pistons that are moved back and forth by compressed air. The non-return valves ensure that the fluid always flows in one direction.

Media diversity of air-operated diaphragm pumps:

Air-operated diaphragm pumps are extremely flexible in terms of the pumped media:

1. Liquids containing solids.
2. Highly viscous substances (e.g. pastes).
3. Shear-sensitive media (e.g. emulsions).
4. Corrosive liquids.
5. Liquid gases and emulsions.

Typical areas of application for air-operated diaphragm pumps:

1. Industry in general:
Pumping solvents, paints, varnishes or oils.
Emptying and transferring from barrels, containers and tanks.

2. Chemical industry:
Dosing acids, alkalis or chemicals.
Pumping media containing solids or with high viscosity.

3. Food and pharmaceutical industry:
Hygienic versions for sensitive liquids such as creams, juices or syrups.
Easy to clean (CIP/SIP-capable versions).

4. Water and waste water technology:
Dosing of chemicals for water treatment.
Sludge pumping or pumping out contaminated liquids.

5. Mining and construction:
Dewatering of pits.
Pumping sludge, cement water or abrasive materials.

Advantages of air-operated diaphragm pumps:

• Can run dry: No damage when pumping air without medium.
• Self-priming: Can also be used with dry pipes.
• Safe for sensitive media: Gentle pumping process.
• Pressure-resistant and robust: Suitable for abrasive, viscous or chemically aggressive media.
• Explosion-proof: Ideal in ATEX zones, as there are no electrics in the pump head.

Air-operated diaphragm pumps are extremely versatile, robust and reliable pump systems that can be used in almost all branches of industry. Their ability to be self-priming, dry-running and explosion-proof makes them particularly attractive for demanding and safety-critical applications.

Here you will find an overview of the most important criteria to look out for when purchasing air-operated diaphragm pumps:

Purchasing air-operated diaphragm pumps requires special technical and application-specific know-how. Due to their versatility, robustness and suitability for critical media and demanding operating conditions, selecting the right model is crucial for safe, efficient and economical operation.

• Before purchasing air-operated diaphragm pumps, it should be clarified exactly for which application the pump is to be procured:
• What is to be pumped? Which medium, with which viscosity? Are flammable liquids or chemicals involved? Are solids to be expected in the medium?
• What are the operating conditions? What is the temperature at the place of use? What is the environment like? Is explosion protection necessary due to the medium?
• What is the desired flow rate and delivery pressure?
• These basic data determine the selection of the pump size, the materials and the overall pump type.
• The chemical resistance of the pump must be matched to the pumped medium:
• Housing material: e.g. aluminum, stainless steel, PVDF, or polypropylene?
• Diaphragm material: e.g. PTFE, EPDM, NBR or Santoprene?
• Valve systems: Ball or flap bearing, depending on the medium (pure, solids-laden, viscous)?
• The wrong choice of material can lead to rapid wear or even dangerous leaks.
• It is important that the pump is designed for the required flow rate and operating pressure:
• Flow rate per minute? Compressed air requirement? Maximum back pressure (e.g. for long lines)? Suction height (self-priming or not)?
• An oversized or undersized pump leads to a loss of efficiency or excessive wear.
• Even if compressed air is available, the consumption should be evaluated:
• How efficiently is the air control valve working? Is the pump equipped with an energy-saving changeover mechanism? Are there options for cycle control or for adapting to fluctuations in demand?
• Operational safety and ATEX conformity for use in potentially explosive atmospheres:
• Does the pump need to be ATEX certified? Do the materials, diaphragms and valves have to be antistatic or conductive?
• Housing and connection components must not generate any ignition sources.
• Explosion protection is an absolute must in many industries such as chemicals, pharmaceuticals, paints and mining.
• Ease of maintenance and spare parts supply is a point that is often underestimated:
• How easy is it to clean or dismantle the pump? Are spare parts quickly available and economically viable? Are there standardized assemblies or modular components?
• Reputable manufacturers offer technical documentation, training and support - this is often more important than a low entry price.
• In critical processes, a reliable replacement pump often counts for more than pure product availability.
• Total cost of ownership (TCO). Professional purchasing always takes the long-term costs into account, not just the initial purchase.
• Pay attention to documentation and conformity such as CE marking, ATEX certification, safety data sheets, installation and operating instructions, pressure test certificates, material certificates, performance data sheets.
• These documents are often also required for internal QM or safety approvals.

Purchasing air-operated diaphragm pumps requires far more than just a look at the price. A holistic understanding of the specific application, the media properties, the operating environment and the technical requirements is crucial. The pump can only work reliably, efficiently and safely if all these factors are taken into account in the selection process.

Air-operated diaphragm pumps can be purchased from various suppliers. You will find comprehensive information on manufacturers and suppliers of Air Operated Diaphragm Pumps around the world on Exportpages.