Air Operated Diaphragm Pump Operation and Selection

When you search for a pump which runs on air power (compressed air). Do not use any electrical means, which can be carried over easily. Even it need not require any priming operation during its startup, then you should go for an air operated diaphragm pump. It is used in a remote area where there will be now power supply erected. But runs by means of compressed air supply. From a production source instead of using power by installing all electrical cabling an air supply hose is used with pressure around 2.5 kg to run the diaphragm pump.

Diaphragm pump application

In some cases where the area is dedicated to the storage of all inflammable substances. As per safety most of the electrical sockets and electrical linings are avoided. The diaphragm pump is completely explosion proof. If in need of transporting liquid or any viscose material away from the work spot. For example, in drilling or excavation operation there are chances of mud and water slurry generation at work environment. Air operated diaphragm pump is the easy way of pumping out this material. Actually, diaphragm pumps can handle thick slurry, liquids with high coarse and viscous fluids. Most of the paint and varnish, porcelain, automobile, food, chemical and pharmaceutical industries use it as and when. In the situation of pumping out chemicals from barrels or drums to a storage tank, it can operate without priming operation. Its application increased for ground and underwater as well as river side’s water pumping and mostly at building sites.

If you have an air compressor in your garage or at your workplace than better-used air operate diaphragm pump instead of centrifugal pump. Its operation and maintenance cost is less than other pumps because it is oil free. Its design is based on the reciprocating model. It produces high head with less power and does not require any NPSH for ground-level operations.  If the application is process oriented in the small-scale process and experimental works if a residual vapour is to be removed in limited quantity and even to create a vacuum to the system, air operated diaphragm pump can handle the work easily. Because it creates a vacuum by sucking the vapours from the system due to its positive displacement character. By adjusting the air flow the pumping flow rate can be varied. It will not damage even it is operated in a dry condition which is not in case of a centrifugal pump.

Air operated diaphragm pump is available in different types of MOC (material of construction) like polypropylene with Teflon, cast iron, aluminium with Teflon, elastomers, stainless steel with neoprene. Based on the factors like pumping fluids, size of particles in the fluid, the temperature of fluid and process application (like food and pharmaceutical process demand food grade materials only), the pump should be selected.

In overall, the classification is done metal pumps, plastic pumps, stainless steel pumps and special design (combination of others) pumps.

  • Metal-air operated diaphragm pump is used for oil and lubricant, building construction sites, wastewater, varnish and paints, mining industries.
  • Plastic air operated diaphragm pump can handle acid and corrosive fluids in paper and timber, coating, alkali and galvanic industries.
  • Stainless steel air operated diaphragm pumps are preferred for food and pharmaceutical industries, which is made by FDA approved materials. It is selected for dairies, cosmetic, beverage and biotechnology industries.

Other advancements made to it are double diaphragm pump for high-pressure applications and reach head up to 152 meters of water.