Pneumatic pumps use compressed air to move fluids. This basic concept uses compressed air to propel mechanical items such as pistons or diaphragms to develop the liquid flow. Such gas, often in the form of compressed air from an external compressor, is supplied to a chamber that puts pressure on the mechanical part. This pressure pushes the part and moves the fluid, forcing it to circulate within the system. Pneumatic pumps are some of the most reliable and easy to control Pumps, and they pump most fluids, including corrosive and viscous liquids.
How Do Pneumatic Pumps Work?
A pneumatic pump takes compressed air, which is changed to mechanical energy that can transport fluids. These pumps use a double-piston system in which one piston has a smaller diameter than the other. The pistons are separated by an air-tight chamber, which may contain a liquid or compressed gas. Compressed gas applies an external pressure on the large diameter cylindrical piston and then on the intermediate chamber of gas/liquid. A small piston develops enhanced force, translating to powerful mechanical performance. Here’s a step-by-step breakdown of how pneumatic pumps typically work:
Air Compression and Entry: The process begins with compressed air being fed to the pump from an external air compressor. Some of this compressed air goes to the pump’s air chamber.
Mechanical Movement: Depending on the type of pump, compressed air acts against the diaphragm, piston, or bellow. In a diaphragm pump, air pressure operates on the diaphragm to create a pumping action, while piston pumps use a piston.
Fluid Displacement: As the diaphragm, piston, or bellows move, a low-pressure area is formed. This vacuum sucks fluid into the pump chamber through an inlet valve. The fluid is expelled through an outlet valve when the diaphragm or piston moves back.
Cycle Continuation: The pump is designed to repeat this cycle continuously. Air is supplied and released in cycles to make the mechanical part oscillate. In each movement cycle, more fluid is attracted and pushed out, creating a continuous flow.
Valves and Flow Control: Check valves are often used at the inlet and outlet to ensure the fluid flows in the correct direction and does not backflow. Adjusting the air pressure can control the pump’s flow rate, allowing precise control over the pumping process.
Unique Features of Pneumatic Pumps
Pneumatic pumps stand out in the industrial world due to several unique features that make them highly versatile, reliable, and safe for various applications. Some of these distinctive characteristics include:
- Explosion-Proof and Safe for Hazardous Environments
Pneumatic pumps do not use electricity. Instead, they use compressed air, making them safe for chemical plants, mining operations, and oil refineries. Their design reduces the possibility of generating dangerous sparks or electrical faults when working with flammable gases or liquids.
- Self-Priming Capability
Many pneumatic pumps are self-priming and will begin pumping fluid without needing to be manually primed or filled with fluid. This feature is useful in cases where the pump may need to start drying or when air gets into the system.
- Ability to Handle a Wide Range of Fluids
Pneumatic pumps are suitable for various fluids that can be highly viscous, abrasive, or corrosive. They can pump water, thick slurries, aggressive chemicals, and other fluids containing solids or debris. Due to such attributes, they can be used widely in wastewater treatment, chemical processing, and food and beverage processing industries.
- Variable Flow and Pressure Control
Controlling the air supply pressure makes adjusting the pneumatic pump flow rate and pressure easier. This means that the rate and volume of pumping can be accurately managed, enabling the pump to be designed to handle a given set of circumstances. This is valuable in applications where it is necessary to accurately meter quantities or when conditions vary often.
- Durability and Low Maintenance
Pneumatic pumps are very reliable, designed with strong materials, and usually long-lasting, so they don’t need regular servicing. They are easier to manufacture comparing electric pumps, which have many parts that are susceptible to wearing out. Furthermore, when there are no electrical components, the chances of having mechanical problems are also minimised.
- No Heat Generation
Unlike electric pumps, pneumatic pumps do not generate considerable heat during operation. This is an advantage in process productions where temperature adjustment is crucial, as it helps minimise the use of extra coolants. It also explains the pump’s special suitability for handling heat-sensitive products.
Types of Pneumatic Pumps
Pneumatic pumps are categorised into several types, each tailored to address specific industrial needs. The most common types include:
1. Diaphragm Pumps
The diaphragm pump mechanism involves a flexible diaphragm actuated by compressed air, which results in a pumping action. During the movement of the diaphragm, it forms a vacuum which sucks the fluid into the pump, and during the return movement of the diaphragm, the liquid is ejected. Because of these pumps’ hermetic sealing capabilities, they are most suitable for dealing with aggressive chemicals, slurries, and high-viscosity fluids. This makes it ideal for chemical processing, water treatment, and food processing industries.
2. Piston Pumps
Piston pumps employ a piston powered by compressed air to develop pressure for moving fluids. The piston is in a reciprocating motion, and such pumps are very effective for high pressure since the fluid gets forced into and out of the pump chamber. They can handle high viscosity and are usually applied in the oil and gas sectors where a level of accuracy in flow and pressure and high-pressure rates are inevitable.
3. Bellow Pumps
The working mechanism is similar to diaphragm pumps, but bellow pumps use a bellows mechanism instead of diaphragms. The air stored in the cylinder expands and contracts the bellows, hence moving the fluid. These pumps are often selected for use where contamination issues are a concern, for example, in the production of pharmaceuticals or in a laboratory where the purity of the fluids is critical.
4. Vane Pumps
Vane pumps are compressors that use vanes mounted on a rotor and rotate to force the fluid through the pump. The vanes move in and out of slots in the rotor and form a set of communicating chambers. However, the total volumes of these chambers vary as the rotor rotates. This design facilitates a smooth flow of the fluid, and therefore, vane pumps are ideal for low- to medium-viscosity fluids. They are commonly used in fuel transfer, lubrication systems, and hydraulic operations.
Applications for Pressure-Driven Flow Control
Based on fluid pressure, pneumatic pumps are widely used in almost all industries because of their advantages, such as pneumatically operated flow control, safety and ease of use, and adaptability to various kinds of fluids. Here are some key applications:
Chemical Processing
Flow control is critical in chemical processing, as chemicals are usually corrosive and hazardous; when in valves and are highly viscous fluids. Pneumatic pumps safely and smoothly transfer acids, bases, solvents, and a number of other strong and potentially dangerous chemicals. Their explosion-proof feature makes them handy for handling flammable substances within a given production line.
Wastewater Treatment
Wastewater treatment plants rely on pneumatic pumps to manage sludge flow, slurry, and other thick fluids. They are employed in dosing chemicals, pumping sludge, and handling fluids containing abrasives or solids. Pneumatic pumps are valuable in this industry because they can work with liquids of different viscosities and have self-priming capabilities.
Food and Beverage Production
Product purity is a very sensitive area, especially in the food and beverage production industry. Syrups, sauces, oils, and other liquids used in food preparation are pumped using Pneumatic pumps. Pneumatic pumps offer a contamination-free operation. They also allow accurate flow regulation for enhanced quality and hygiene. Besides, they are commonly used in applications where the products being handled are delicate or sensitive.
Pharmaceutical Manufacturing
The chemical processes used in the pharmaceutical industry require high accuracy and hygiene. Pneumatic pumps transport ingredients, manage dosing, and move sensitive fluids under sterile conditions.
Oil and Gas Industry
The oil and gas industry employs pneumatic pumps to transfer and measure hydrocarbons, including crude oil, petroleum products, and others. These pumps are useful in every process that involves close control of the flow rate and pressure, such as injection processes, chemical injection, and pipeline systems.
Automotive Industry
In automobile production, pneumatic pumps transport fluids such as lubricants, coolants, and other fluids used in automobile construction and repair. Their precise flow control capabilities ensure that fluids are delivered accurately and efficiently, reducing waste and improving process efficiency.
Paint and Coating Applications
Pneumatic pumps are used in the paint and coating industry to transfer and apply paints, varnishes, and other coatings. Their durability in working with high-viscosity fluids and their ability to maintain steady, vibration-free flow are essential factors for achieving quality finishes.
Pneumatic Pumps from Yamada by Ocean
Being the leading engineering company in Oman, Ocean provides a variety of high-quality pneumatic pumps, such as pneumatic pumps from Yamada. Ocean distributes Yamada pneumatic pumps, which are reliable and efficient and can easily withstand some challenging conditions encountered in industrial fields. These pumps are equipped with features such as leak detection, durability in wearing parts, and easy maintenance.