The essential role of air preparation units in pneumatic system performance
For proper operation, pneumatic systems require air preparation units – also known as FRL units - as vital components. By supplying compressed air of optimal quality, these units enhance the efficiency and service life of pneumatic components while significantly reducing downtime.
Standard air treatment components
An air treatment or preparation unit is composed of at least some of the following elements:
Depending on the application, extra components such as residual pressure relief valves, soft start-up valves, membrane air dryers or pressure switches may be incorporated.
The modular nature of SMC’s designs makes it possible to create customised configurations that satisfy industrial requirements while keeping layouts compact and efficient.
Why use a compressed air treatment unit?
The compressed air from compressors commonly includes contaminants such as debris, oil and moisture, which can negatively affect the efficiency and longevity of pneumatic systems. Particles may also enter the system due to erosion in the pipelines.
Typical issues caused by contaminated compressed air:
- Deterioration of lubrication
- Blocked passages or pilot holes
- Failure to start in low-temperature conditions (freezing)
- Internal mechanical malfunctions
- Formation of water inside the system
- Pressure drops, clogged filters and stuck auto drains
- Leaks caused by damaged seals
- Reduced product quality, especially in processes such as painting, blowing, printing, etc.
Contaminated compressed air can also affect automation components, including:
- Valve and actuator failures due to grease washout
- Rust inside the ducts causing seized auto drains
- Damaged seals caused by air leaks
- Corrosion in regulators
- Excess moisture causing system saturation
Solution: Air preparation (FRL) units make sure compressed air is provided in optimal condition by:
- Removing particles, moisture and oil
- Regulating pressure to match system requirements
- Adding lubrication to the air to protect pneumatic components
Ensuring correct air quality allows these units to boost equipment performance, avoid system malfunctions and increase process efficiency in industrial settings.
How to choose the correct air preparation unit?
The selection of a suitable air treatment FRL unit involves evaluating several factors carefully:
- Specific application: Depending on the application, the necessary air quality may differ. Our air treatment guide helps you identify the adequate air quality class for your application and choose the products that fit the most your installations.
- Main factors to assess when choosing a maintenance unit:
- What connection size is required? Determining the necessary peak flow is advisable. With our flow rate calculation software,calculate the peak flow and size the components of the maintenance unit accordingly.
- Is a pressure relief valve required? We advise to add one to allow the machine to be pressurised or depressurised, such as during industrial maintenance.
- Is pressure regulation needed? To set the network pressure to the ideal level for your equipment, a pressure regulator is generally necessary. This can be achieved manually or remotely using electro-pneumatic regulators.
- Is a sensor needed to measure flow? Although not essential, adding sensors is advisable to monitor the state of the system and support efficiency-based decision-making in industrial operations.
- Is it necessary to use an air lubricator? Since most SMC pneumatic actuators are already lubricated, a lubricator is not always needed. However, it is advisable to use one for high-frequency applications or actuators that lack internal lubrication.
To build an air treatment unit that fits your requirements, try our airline equipment configurator, as it enables you to design a solution exactly adapted to your line.
What maintenance is required for an FRL unit?
Ensuring correct filter maintenance is crucial, since saturated cartridges often lead to malfunctions in compressed air network components, such as actuators, valves and maintenance units.
SMC recommends replacing the filter cartridges every 2 years, or earlier if the pressure drop exceeds 0.1 MPa (1 bar), to ensure optimal performance.
Contact our team of experts to find the ideal air treatment unit for your specific application requirements.
