Pneumatic pumps are a type of device that is driven by compressed air to transfer fluids from one place to another. In this article, we will explain the mechanics and operation of a pneumatic pump, its components, working process and the most common applications.
If you are not sure if this is the pump you need, see our article 7 tips for choosing a metering pumpFor further information, please contact us.
Types of pneumatic pumps
There are different types of pneumatic pumps, the most common of which is the double diaphragmwhich will be discussed in this article. These use a plunger or piston mechanism to transfer liquids through a cylindrical chamber.
These pumps consist of two pumping chambers and two diaphragms connected by a central shaft, called a distributor. The injection of compressed air causes the displacement of these diaphragms with an alternating compression/suction movement in each of the two chambers: when the shaft is moved to one side, the diaphragm on that side is compressed against its respective pumping chamber, pushing the liquid forward, while on the opposite side the opposite happens, sucking the liquid in. Each of the chambers is equipped with suction and discharge valves to allow unidirectional movement of the liquid.
These pumps can be manual or automatic (controlled by means of a solenoid valve)The new electric motors offer an alternative that stands out for its economy, flexibility and a comparatively higher level of safety compared to electric motors.
Basic components of a pneumatic pump
A typical pneumatic pump consists of the following basic components:
Pumping chamber:
It is the space where the diaphragms are housed. It is the place where the pumping of the liquid occurs.
Diaphragms:
They are flexible membranes that separate the pumping chamber into two sides: the suction side and the discharge side. They are made of strong and flexible materials, such as elastomers. Both diaphragms are driven by a piston to which they are attached.
Ball valves:
One on each side of each diaphragm. These valves allow unidirectional flow of liquid, ensuring that liquid enters at the inlet and exits at the outlet.
Liquid inlet and outlet:
These are the connection points through which the liquid enters and leaves the pumping chamber.
Air connection:
Compressed air inlet point that drives the diaphragms.
Operating process of a pneumatic pump
The operating process of a pneumatic pump consists of the following steps:
Compressed air inlet:
The compressed air from the air compressor is directed to the pump body via the air inlet connection.
Piston and diaphragm movement:
Compressed air enters the pump's air chamber, causing the piston to move inside the pump body which, in turn, drives the diaphragms inside the two pump chambers.
Fluid inlet:
As the piston and diaphragms move, they create a pressure differential within the pump, causing fluid to be drawn through the inlet port and into the pump chamber.
Fluid discharge:
Fluid is expelled from the pump chamber through the fluid outlet port, driven by the movement of the diaphragms.
Valve operation:
Valves inside the pump direct the flow of fluid, ensuring that it moves in the intended direction and preventing backflow.
Continuous cycle:
The fluid intake and discharge process continues while the compressed air supply remains active, allowing a continuous flow of fluid through the pump.
Common applications of pneumatic pumps
Pneumatic double diaphragm pumps are versatile tools that find crucial applications in a variety of industries. Some of the most important applications are listed below:
- Chemical Industry
- Double diaphragm pumps are essential for the safe transfer of chemicals, from solvents to corrosive compounds. Their ability to handle a wide range of chemicals makes them an essential choice in this sector.
- Food sector
- In the food industry, where hygiene and safety are a priority, these pumps are ideal. They are used for handling liquids such as syrups, sauces and other ingredients, ensuring product integrity without risk of contamination.
- Wastewater Treatment
- In water treatment operations, double diaphragm pumps are effective for handling wastewater with suspended solids or for transferring biological or chemical sludge. Their robust design and ability to handle dense or viscous fluids makes them a reliable choice.
- Pharmaceutical industry
- In pharmaceutical environments, where sterility is crucial, these pumps are used for the transfer of liquid pharmaceutical products. The cleanability and resistance to contamination make them ideal for this sector.
- Paint Manufacturing and Processing
- In the manufacture of paints and coatings, double diaphragm pumps are essential for the precise transfer of pigments and viscous liquids. Their ability to handle abrasive substances without damaging them makes them valuable in this context.
- Petrochemical industry
- In petrochemical applications, these pumps are used for the safe handling of products such as oils, fuels and lubricants. Their corrosion resistance and ability to handle viscous fluids are key attributes in this environment.
- Mining Processes
- In the mining industry, double diaphragm pumps are used for handling slurries and abrasive substances. Their robustness and ability to handle solids in suspension make them essential tools for mining operations.
These applications demonstrate the adaptability and efficiency of double diaphragm pumps in a variety of industrial environments, making them a reliable choice for transferring liquids in demanding conditions.
Advantages of pneumatic pumps
– Can run dry without damage.
– Reliability: Pneumatic pumps have a simple design with fewer moving parts, making them reliable and easy to maintain.
– Accepts liquids of very high viscosityeven with suspended solids.
– Self-priming: Pneumatic pumps are self-priming, which means that they can draw in fluid, even if the pump is not initially filled with liquid. They have a high suction capacity.
– Safety in use: as they do not require electricity, they are ideal for hazardous environments (ATEX).
– Simplicity: Pneumatic pumps are easy to install and use, even without special technical knowledge.
- Capacity for pumping delicate materials without damaging them.
Disadvantages of pneumatic pumps
- Less precision compared to other pump types.
- They may be less energy efficient.
- Higher noise level.
Pneumatic pumps: an efficient solution
Pneumatic pumps are valuable tools that harness the power of compressed air to facilitate the transfer of fluids in a wide range of applications. Their simplicity, reliability and efficiency make them indispensable in a variety of industries, contributing to efficient fluid handling processes.
In short, air-operated diaphragm pumps require minimal maintenance and are able to run smoothly even under difficult conditions. This means that maintenance and repair costs are reduced to a minimum, and the pump can be used for a long time without problems.
Link to Seko Duotek pumps:
