Pneumatic diaphragm pump (air operated diaphragm pump) is a new type of conveying machine, which uses compressed air as the power source. It can absorb all kinds of corrosive liquids, liquids with particles, high viscosity, volatile, flammable and highly toxic liquids.
Materials of pneumatic diaphragm pump
There are four kinds of materials for pneumatic diaphragm pumps: engineering plastics, aluminum alloys, stainless steel, and cast iron. The pneumatic diaphragm pump adopts nitrile rubber, neoprene rubber, fluorine rubber, PTFE, PTFE, etc. according to different liquid media to meet the needs of different users. It is placed in various special occasions and used to pump various media that cannot be pumped by conventional pumps, and satisfactory results have been achieved.
See more: What are the materials of the air-operated diaphragm pump?

Applications of pneumatic diaphragm pump
Because the air-operated diaphragm pump has many advantages, the air-operated diaphragm pump is gradually invading the market of other pumps since its birth, and occupies a part of it. Pneumatic diaphragm pump has occupied an absolute dominant position in painting and ceramic industries. In some other industries, such as environmental protection, wastewater treatment, construction, sewage, and fine chemicals, it is expanding its market share and has an irreplaceable position with other pumps.
The working principle and characteristics of pneumatic diaphragm pump
The pneumatic diaphragm pump is a volumetric pump that uses compressed air as the power and the volume changes due to the reciprocating deformation of the diaphragm. Its working principle is similar to that of a plunger pump. Due to the characteristics of the working principle of the pneumatic diaphragm pump, the pneumatic diaphragm pump has the following characteristics:
- The pump will not be overheated: compressed air is used as power, and it is a process of expansion and heat absorption when exhausting. When the pneumatic pump is working, the temperature is reduced, and no harmful gas is discharged.
- No electric sparks will be generated: the pneumatic diaphragm pump does not use electricity as power, and prevents electrostatic sparks after grounding.
- It can pass through particle-containing liquid: because it works in a positive way and the inlet is a ball valve, it is not easy to be blocked.
- The shear force on the material is extremely low: the pump has little stirring effect on the material when it is working. It is suitable for the transport of unstable substances.
- The flow can be adjusted. A throttle valve can be installed at the material outlet to adjust the flow.
- Function of self-priming.
- It can be run dry without danger.
- Suitable for diving work.
- The fluids that can be transported are extremely wide, from low viscosity to high viscosity, from corrosive to viscous.
- There is no complicated control system, no cables, fuses, etc.
- Small size, light weight, easy to move.
- No lubrication is required, so maintenance is easy. Will not contaminate the working environment due to dripping.
- The pump can always keep working efficiently. There is no loss of efficiency due to wear.
- 100% energy utilization. When the outlet is closed, the pump stops automatically. There is no risk of equipment movement, wear, overload, heat generation.
- No dynamic seal, easy maintenance to avoid leakage, no dead point during work.
See more: Advantages of air operated diaphragm pumps
Application areas of pneumatic diaphragm pumps
Industries | Examples of fluids |
---|---|
Chemical industry | Acids, alkalis, solvents, suspended solids, disperse dyes, etc |
Petrochemical industry | Heavy oil, grease, mud, sludge, etc |
Coating industry | Resins, solvents, colorants, paints, etc |
Daily chemical industry | Detergents, shampoos, lotions, lotions, hand creams, surfactants, etc |
Ceramic industry | Mud, porcelain slurry, lime slurry, clay slurry, etc |
Mining industry | Coal slurry, magma, mud, mortar, lubricating oil, etc |
Water treatment | Lime slurry, soft sediment, sewage, chemicals, waste water, etc |
Food industry | Liquid semi-solid, chocolate, brine, vinegar, syrup, vegetable oil, soybean oil, honey, etc |
Beverage industry | Yeast, syrup, concentrate, gas-liquid mixture, wine, fruit juice, corn steep liquor, etc |
Pharmaceutical industry | Solvents, acids, alkalis, plant extracts, ointments and other pharmaceutical liquids, etc |
Paper industry | Binders, resins, paints, inks, pigments, hydrogen peroxide, etc |
Electronics industry | Solvents, electroplating liquids, cleaning liquids, nitric acid, waste acids, corrosive acids, polishing fluids, etc |
Textile industry | Dye chemicals, resins, glues, etc |
Construction industry | Cement slurry, ceramic tile adhesive, rock slurry, ceiling paint, etc |
Automotive industry | Polishing emulsions, oils, coolants, automotive primers, oil emulsions, varnishes, varnish additives, degreasers, paints, etc |
Furniture industry | Adhesives, varnishes, solvents, colorants, white wood glue, epoxy resins, starch adhesives, etc |
Metallurgy, foundry and dyeing industry | Metal pulp, hydroxide and carbide pulp, dust washing pulp, etc |
Pneumatic diaphragm pumps (AOD pumps) vs other Types of Pumps
Pneumatic one-way diaphragm pump has six advantages such as reliable quality, long service life, low noise, small vibration, never crash, and fine workmanship. It can not only pump flowing liquid, but also transport some medium that is not easy to flow. It has many advantages of conveying machinery such as self-priming pump, submersible pump, canned pump, mud pump and impurity pump.
Pneumatic diaphragm pump (AOD pump) | Gear Pump |
Dry Run without damage | Can not be ran dry |
Handle Abrasives | Can not handle abrasives |
Designed for varying flow, viscosity and head conditions | Limited ability to handle varying viscosity, thixotropic or non Newtonian liquids |
Pump pauses during zero flow without energy consumption at dead head. Restarts once closed valve opens | Relief valve required if deadheaded with only limited time for using bypass |
No rotating or close wear parts which once wear experience large drops in flow | Many Rotating and close tolerance wetted parts |
Pneumatic diaphragm pump (AOD pump) | Progressing Cavity Pump |
Dry run without damage | Can not dry run |
Fewer less expensive wetted wearing parts | Expensive rotating and close tolerance parts |
Maintenance relatively easy | Maintenance time consuming, labour intensive. Usually required to be taken off site for repair as specialist tools and knowledge required for maintenance. |
Virtually no slip with thin liquids such as water | Slip increases with low viscosity fluids |
Pump pauses during zero flow without energy consumption at dead head. Restarts once closed valve opens | Relief valve required if deadheaded with only limited time for using bypass |
Compact design | Larger unit with gearbox |
Handle a wide range of temperatures | Limited temperature handling capability |
Pneumatic diaphragm pump (AOD pump) | Vane Pump |
Dry Run without damage | Limited dry run |
Fewer less expensive wetted wearing parts | More rotating and close tolerance parts |
Pump pauses during zero flow without energy consumption at dead head. Restarts once closed valve opens | Relief valve required if deadheaded with only limited time for using bypass |
Handles solids as large as inlet | Limited solids handling |
Handle Abrasives | Can not handle abrasives |
Pneumatic diaphragm pump (AOD pump) | Lobe Pump |
Self Priming up to 7.6M | Limited suction |
No rotating or close wear parts which once wear experience large drops in flow | Many Rotating and close tolerance wetted parts |
Pump pauses during zero flow without energy consumption at dead head. Restarts once closed valve opens | Relief valve required if deadheaded with only limited time for using bypass |
Handle Abrasives | Can not handle abrasives |
Handles solids as large as inlet | Limited solids handling |
Brands of pneumatic diaphragm pumps
WILDEN®, SANDPIPER®, ARO®, VERSA-METIC® are the most famous brands for pneumatic diaphragm pumps(AOD pumps). If you want to buy these brands pumps and accessories/spare parts. Please feel free to contact us: sales@northstarpump.com