Pneumatic Conditioners (FRL Units)

Oil residue, water vapor, dust, and dirt in the air coming from the compressor, if allowed to reach the system, prevent pneumatic components from working properly, reduce their efficiency, and cause them to wear out quickly.

To prevent this, an air conditioner (FRL unit) is placed before every pneumatic machine or system.

A pneumatic conditioner consists of four elements:

The filter removes solid foreign particles from the air coming from the compressor. If a water separator is present in this section, condensed water is also separated out. Water droplets that condense as they strike the filter bowl collect at the bottom of the bowl. Automatic or manual drain mechanisms are used to empty this accumulation.

For applications that don’t require precision, 40μ (1μ=0.001mm) filters are sufficient. If the filter will be used above 50°C or above 10 bar, if solvent vapor is present in the environment, or if high flow-rate permeability is required, filters with a metal housing should be selected.

The job of the pressure-reducing (regulating) valve is to reduce the fluctuating inlet pressure, which comes from the compressor and is larger than the desired value, to a lower, nearly constant and adjustable output pressure. It also prevents pressure fluctuations in the system.

Sending air at different pressures to the user means that variables such as speed and force will also differ; naturally, the work done at the end of each cycle will vary. This is why preventing pressure fluctuations is important.

The lubricator’s job is to mix a small amount of oil, in mist form, into the compressed air. This prevents pneumatic components from wearing due to friction. Too much oil should not be mixed in during this process, as it can clog precision orifices and cause environmental pollution.

Lubrication quality depends on the pressure difference between the inlet and outlet caused by the air striking an obstruction. As this implies, this type of lubricator operates based on pressure difference, which results in energy loss.

As flow rate increases, the pressure difference increases. As the pressure difference increases, the amount of lubrication increases. Because there is a defined ratio between flow rate and lubrication amount, this type of lubricator is called a “proportional lubricator.”

To select the lubricator best suited to our needs, the selection should be made according to flow rate–pressure drop charts. If a lubricator larger than necessary is selected, sufficient pressure drop will not be achieved and lubrication will not occur. If a lubricator smaller than necessary is selected, an excessive pressure drop will occur, resulting in energy loss.

A pressure gauge is a mechanical measuring instrument that displays the measured pressure value on a dial.