What are the main components of FFU? Detailed explanation of fans, filters and control systems

The FFU seems to be a relatively compact clean air device, but when you take it apart, you will find that it is actually an air filtration system with multiple core components working together.

A common FFU mainly includes:

Cabinet | Motor | Fan | HEPA/ULPA filter | Control system | Air inlet structure | Air outlet structure | Electrical components

These components are not simply installed in a box.

The real design logic of FFU is:

Target air volume and wind speed → Determine the air treatment needs → The filter generates resistance → The fan provides the corresponding air volume and pressure → The motor drives the fan → The control system manages the operating status → The box forms a reasonable air duct → The whole machine outputs filtered air

Therefore, the key to understanding the FFU structure is not only to know 'what's inside', but more importantly, to understand why these components need to match each other.。

1. What are the main parts of the FFU structure?

First, let’s quickly understand the basic composition of FFU through a table.

The specific internal structure of FFU with different sizes, different air volumes and different application scenarios will be different.

For example, ordinary clean room FFU and ultra-thin FFU/EFU installed inside semiconductor equipment may have completely different requirements for cabinet height, fan size, filter structure and electrical layout.

2. Is the FFU cabinet just a shell?

no.

The box looks like just the outermost metal structure of the FFU, but it also plays the role of structural support and internal air organization .

The FFU cabinet mainly needs to be completed:

Fixing fans and motors | Installing filters | Arranging control and electrical components | Forming internal air channels | Installing with clean rooms or equipment

Therefore, the cabinet design will be directly affected by the installation space.

Conventional clean room FFU usually needs to focus on confirming the length, width and ceiling installation method.

Device-side applications often also focus on:

Overall height | Air inlet position | Air outlet direction | Fan layout | Electrical interface location | Maintenance space

Especially in semiconductor equipment, EFEM, SMT equipment and automation equipment, the installation space may be relatively compact. In this case, the FFU box structure needs to match the equipment itself.

3. What is the function of FFU fan?

The fan is one of the core components in the FFU aerodynamic system.

After FFU is running, the fan needs to keep the air flowing and overcome the air resistance generated by the filter and the system.

It can be simply understood as:

The fan rotates → air enters the FFU → air volume and pressure are established → air overcomes filter resistance → filtered air is sent out from the air outlet surface

Therefore, FFU fan selection cannot only look at the 'maximum air volume'.

Also need to consider:

Pay special attention to:

The maximum air volume tested by the fan alone is not equal to the actual air volume of the FFU complete machine after the filter is installed.

What should really be concerned about is the operating status of the fan under actual resistance conditions after it is installed in the FFU.

4. Why does FFU need a motor?

The motor is responsible for driving the fan impeller to rotate.

Therefore, the motor and fan actually form the power system of the FFU.

The basic relationship can be expressed as:

The motor inputs electric energy → drives the fan impeller → establishes air flow → overcomes the resistance of the filter and system → outputs the target air volume

FFU can adopt different motor and drive solutions according to product and project requirements, such as AC, DC, EC, etc.

The different options are:

Control method | Speed ​​regulation capability | Input power | Operating characteristics | System cost

There may be differences in other aspects.

Therefore, when choosing FFU, it is not recommended to simply judge 'which motor is better', but to match it according to the actual operation requirements of the project.

5. Why are fans and motors best considered together?

Because what FFU really needs is a power system that meets the working conditions of the entire machine.

For example, a project requires:

Specific size + designated air volume + designated air speed + H14 filter + certain system resistance

At this time, the fan and motor need to be matched around this operating point.

If you only choose a fan with a large air volume, you do not consider:

Filter resistance | Air duct structure | Fan efficiency | Motor power | Speed ​​regulation method

The final operating status of the complete machine may not meet the project requirements.

Therefore, a more reasonable design idea for the FFU power system is:

Project requirements → Determine operating conditions → Match fans → Match motors → Complete machine verification

6. What is the responsibility of the HEPA/ULPA filter in FFU?

The fan solves 'how the air flows', and the filter solves 'how the air filters'.

FFU can often be configured with HEPA or ULPA filters depending on project requirements.

Filter selection should not just look at the efficiency level.

Also need attention:

Filtration efficiency | Rated air volume | Initial resistance | Size | Filter material | Structure | Sealing method | Usage environment

Because the filter itself is also one of the sources of resistance in the FFU air system.

7. Why does filter resistance affect FFU air volume?

This is a very critical point in understanding the FFU structure.

Air creates resistance as it passes through the filter.

The fan needs to overcome this resistance to maintain the required air flow.

therefore:

Filter resistance changes → System resistance changes → Fan operating point changes → FFU actual air volume may change

This is why you cannot simply replace the H14 filter with filters of other structures or levels, and then think that other parameters of FFU do not need to be adjusted at all.

If the filter resistance changes significantly, it is necessary to re-confirm the operating status of the fan and the entire machine.

8. What is the function of FFU control system?

For a single FFU, the control system can be responsible for basic start, stop and speed adjustment.

But when there are dozens or hundreds of FFUs in the project, the importance of the control system will increase significantly.

Depending on the project configuration, the FFU control system can achieve:

Start and stop control | Speed ​​adjustment | Partition management | Working mode | Duty mode | Single machine management | Running status view

For example, a clean room may have different requirements for FFU operating status during normal production and non-production periods.

At this time, the equipment operation mode can be adjusted according to the project design without the need to go to the site one by one.

9. Are the control methods for a small amount of FFU and hundreds of FFU the same?

Usually not exactly the same.

Small projects with a small number can use relatively simple control methods.

Aili Industrial can configure corresponding controllers according to small FFU/EFU projects. For example, the 86-type controller can be used to control up to 32 devices, and can perform area, wind speed, start-stop and status management according to the configuration.

When the number of FFU further increases, computer group control can be considered based on the project.

Computer group control can be carried out according to the system design:

Partition setting｜Working speed setting｜Duty speed setting｜Start and stop management｜Single machine control｜Running status management

This is more suitable for a large number of FFU systems.

10. What impact does the FFU air inlet structure have?

The air inlet structure is responsible for introducing air into the FFU.

While it may seem like a simple structure, it affects how the internal air enters the fan.

When designing, you usually need to consider:

Air inlet space | Fan location | Installation environment | Equipment height | Maintenance methods

For conventional clean room FFU, the installation space is usually relatively sufficient.

The space of FFU/EFU on the equipment side may be relatively compact, so the air inlet method, fan layout and overall height need to be considered together.

This is why the equipment-side FFU cannot simply be reduced in size according to the ordinary clean room FFU.

11. Why should uniformity be considered in the FFU air outlet structure?

FFU ultimately needs to send filtered air into the clean area.

Therefore, in addition to 'how much air volume', the distribution of air when it comes out of the air outlet surface is also worthy of attention.

Especially in semiconductor equipment, precision manufacturing and some high-cleaning applications, there may be higher requirements for the uniformity of wind speed on the air outlet surface.

Factors affecting the air outlet status include:

Fan structure | Fan position | Air duct inside the box | Filter structure | Air outlet area | Actual operating air volume

Therefore, FFU cannot only pursue a larger total air volume.

In some applications, wind speed uniformity and airflow stability are also important design parameters.

12. Why does FFU need complete machine testing?

Because the parameters of a single component are qualified, they cannot directly represent the operating status of the entire FFU machine.

For example:

The fan has its own performance curve | The filter has its own resistance | The box will affect the air flow | The control system will change the fan speed

After these parts are assembled together, the real FFU working state is formed.

Therefore, the FFU complete machine needs to pay attention to:

During the manufacturing process of fans and FFU products, Aili Industries will conduct corresponding testing around core components, assembly processes and complete machine operation.

13. Why does Aili Industrial emphasize self-research and manufacturing of FFU core components?

For FFU, the fan, motor, control system, filter and box are not independent of each other.

If one parameter changes, other components may need to be adjusted accordingly.

Aili Industry has established a product system from core components to complete machines around FFU, EFU and clean air equipment, covering:

Motor→Fan→Control system→HEPA/ULPA filter→Sheet metal→Complete machine assembly and testing

The value of this model is mainly reflected in the project matching ability.

For example:

In this way, when facing standard FFU, ultra-thin FFU/EFU, device-side applications, and non-standard projects, components can be matched based on the needs of the entire machine.

14. Do different applications have the same requirements for FFU structures?

no the same.

Therefore, even if it is called FFU, the internal configuration and structure in different applications may not be exactly the same.

15. What internal configurations should you ask when purchasing FFU?

In addition to dimensions and price, it is recommended to confirm at least the following.

If it is a non-standard equipment project, it is also recommended to provide equipment installation space and target operating conditions.

16. Summary of FFU structure selection

If you select from the perspective of the internal structure of FFU, you can understand it in the following order:

Project application → Installation space → Target air volume and wind speed → Filtration level → Filter resistance → Fan air volume and air pressure → Motor and driving mode → Control mode → Box structure → Complete machine test confirmation

The FFU that is truly suitable for the project is not that one component parameter is particularly outstanding, but that the core components are reasonably matched around the actual working conditions.

Aili Industrial develops and manufactures products around motors, fans, control systems, HEPA/ULPA filters, sheet metal and FFU/EFU complete machines. It can configure corresponding products according to clean rooms, semiconductor equipment, electronic manufacturing, lithium batteries, photovoltaics and other clean air projects.

FFU FAQ

What are the main contents of FFU?

FFU usually includes a box, motor, fan, HEPA or ULPA filter, control system, air inlet and outlet structure, and electrical components.

What is the core component of FFU?

Different components perform different functions. The fan is responsible for providing air power, the filter is responsible for filtering particulate matter, the motor is responsible for driving, and the control system is responsible for operation management. Therefore, what is more important is the overall matching of each component.

Is the bigger the FFU fan, the better?

no. The fan needs to be matched according to the target air volume, air pressure, filter resistance, installation space and operating requirements.

Can the grade of FFU filter be changed at will?

It is not recommended to only change the filtering level and ignore other parameters. Changes in filter grade and structure may be accompanied by changes in resistance, and the operating status of the FFU machine needs to be re-confirmed.

Why does FFU need a control system?

The control system is used for equipment start and stop, speed regulation and operation management. A large number of FFU projects can also be partitioned and centrally managed through group control.

Can the height of the FFU cabinet be customized?

It can be matched according to the equipment installation space, fans, filters and structural requirements, but the overall height needs to take into account the air volume, resistance and internal component layout.

Why does FFU need complete machine testing?

Because the fan, filter, box and control system will jointly determine the actual operating status after assembly, individual component parameters cannot fully represent the performance of the entire machine.

Related products

FFU fan filter unit ｜ HEPA/ULPA high efficiency filter ｜ FFU group control system

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What is FFU? Structure, working principle, application scenarios and selection guide