Compressed air filters are applied in condensed air lines to thwart liquid and solid contaminants from entering the machine. Compressed air that leaves a screw or piston air compressor contains large water contents, increased concentration of oil, as well as other contaminants. It is crucial to employ a compressed air filter to remove any present contaminants.
Air line filters work by removing contaminants from pneumatic systems to prevent damaging the equipment, as well as to lessen the production loss because of contaminant-related downtime. The downtime in an industrial plant is pricey, and the common reason for this is usually the outcome of a contaminated and poorly maintained compressed air system.
How Air Line Filters Work
Air line filters work by cleaning compressed air; it strains air to trap solid particles such as dirt, dust, rust, and can also separate liquid such as water and oil that gets entrained in compressed air. Filters are set up in air line upstream of directional control valves, lubricators, regulators, and also air driven devices like air motors and cylinders.
When compressed air is unfiltered, it frequently contains dust, rust, oil, moisture, and other forms of harmful substances that require filtration as soon as possible.
- During the first stages of filtration, compressed air goes through a tube-like mesh filter that creates a clumping effect – bigger particles are absorbed in the filter while the water gets condensed into larger droplets. These droplets will then pass into a separation chamber.
- Compressed air eventually slows down which condenses the particles on a honeycomb-like pad, granting access to water droplets and making them travel to the bottom of the drainage
- From the drainage system, these droplets go through an automatic or electric drain valve to discharge. During this stage of filtration, more than 95% of the water droplets, large particles, and oil are removed.
Types of Filters
- Particulate Filters
– these particulate compressed air filters are used for removal of dust and other types of particles coming from the air.
- Activated Carbon Filters
– Activated Carbon Filters make use of a composite carbon matter that is used for the removal of gas and odor from the air. They are commonly used in factories where food is produced or sometimes, for breathing gas.
- Coalescing Filters
– High oil compressed air coalescing filters remove oil aerosols and water by fusing the aerosols into droplets. This partially happens due to pressure drops and torturous paths.
These coalescers remove both oil aerosols and water from the air stream; also, these coalescers are rated at unrefined contamination through direct blocking. Filtration of dust and dirt particles, water aerosols, and oil to 0.01µm (micrometer) is the most excellent achievement in the industry.
- Cold Coalescing Filters
– These cold coalescing filters are coalescing filters that are operated at around 35 ｰF (2 ｰC), which allows them to become adequate and efficient when removing moisture.
- Compressed Intake Filters
– The intake filters are considered as the first line of defense when it comes to filtering since these filters can easily expel contaminants down to 0.3µm, as well as remove chemical contaminants.
A dirty machine can function properly, yet works at the expense of downstream components. Liquids and contaminants can break the insides of pipes, as well as other pneumatic components available in the system. Also, a lot of pneumatic cylinders and valves have little orifices that can quickly get plugged with contamination.
The quality of air has a significant effect on compressed air systems, so the correct air dryer and adequately treated compressed air will highly improve the productivity, process quality, and system efficiency of the machine.