Focusing on the technical application of integrated high-efficiency air outlets in electronic clean rooms, this type of terminal air supply device is classic and highly efficient, playing an irreplaceable role in modern electronic manufacturing, especially for the renovation of old factories or the upgrade of specific areas.
I. What is an Integrated High-Efficiency Air Outlet?
An integrated high-efficiency air outlet is a terminal air supply device that integrates a high-efficiency filter (HEPA/ULPA), a housing (static pressure box), and a diffuser (air distribution membrane) into a single unit. It connects to the central air conditioning system via ductwork and represents the "last mile" of clean room air treatment.
The main difference from FFU (Fan Filter Unit) is that FFUs have their own fans, while standard integrated high-efficiency air outlets do not come with fans and rely on the central air conditioning system's fan for power. However, there are variants with fans (Fan-Assisted HEPA Box).
II. Application Scenarios in Electronic Clean Rooms
Integrated high-efficiency air outlets are particularly suitable for the following electronic workshop scenarios:
1. ISO Class 7-8 (10,000-100,000 level) clean rooms: As the main terminal air supply device, they are densely or evenly distributed on the ceiling.
2. ISO Class 6 (1,000 level) clean rooms: They can serve as the entire room's air supply device or as background air supply for higher-level clean environments.
3. Local cooling/exhaust compensation for process equipment: Provide compensatory air supply for process equipment that requires exhaust (such as etching machines, diffusion furnaces) to maintain stable room pressure differentials.
4. Upgrade and renovation of old workshops: Adding high-efficiency air outlets and return air walls to existing general air conditioning workshops is a cost-effective and time-saving clean room renovation solution.
5. Small clean rooms or laboratories: Such as metrology rooms, precision analysis laboratories, etc.
III. Core Technical Advantages and Application Value
The choice of integrated high-efficiency air outlets in electronic clean rooms stems from their multiple advantages:
Their core advantages and application values are as follows:
1. Ensure clean air output: Equipped with H13/H14-grade high-efficiency filters, with a filtration efficiency of ≥99.99% for 0.3μm particles, directly providing clean air to electronic workshops, which is the core guarantee for achieving clean room standards.
2. Uniform air distribution: The static pressure box design ensures that air passes uniformly through the entire surface of the filter material, in conjunction with the air distribution membrane or perforated diffuser, avoiding air jets and forming stable turbulent or vertical flow, effectively diluting and exhausting particles.
3. Easy installation and maintenance: Using mechanical pressure tightening, integrated with the ceiling panel module. Filter replacement only requires operation above the ceiling, without affecting production below, making maintenance convenient and downtime short.
4. Broad system adaptability: Relying on the central air conditioning fan, there is no need for separate power supply and control for each air outlet. For large areas and workshops with moderate cleanliness requirements (not ISO Class 5 and above), the overall system energy consumption and initial investment may be lower than the FFU solution.
5. Efficient space utilization: Integrating filtration, air distribution, and delivery functions into one, compact structure, saving space above the ceiling, facilitating the layout of other pipelines (fire protection, electrical, process pipelines).
IV. Key Technical Details and Selection Points
When selecting and applying integrated high-efficiency air outlets for electronic workshops, the following technical details must be considered:
1. Filtration efficiency selection
1.1 ISO Class 8-7 (100,000-10,000 level): H13 efficiency filters are usually selected.
1.2 ISO Class 6 (1,000 level): H14 efficiency filters are recommended.
1.3 Key process areas: If used as background for local ISO Class 5 environments, H14 should also be selected.
2. Sealing method - absolutely crucial
2.1 Liquid seal: Strongly recommended for electronic workshops. Achieving absolute air tightness by embedding the blade into a groove filled with sealing gel, ensuring no leakage, which is key to ensuring cleanliness. During installation, ensure the blade is flat and the sealing gel is fully filled.
2.2 Mechanical pressure + sealing strip: Lower cost, but requires high installation precision, and the sealing strip is prone to aging, with a risk of leakage, requiring frequent leak detection. Only suitable for areas with slightly lower requirements.
3. Housing material
3.1 Cold-rolled steel spray plastic: Most common, cost-effective, suitable for general electronic workshops.
3.2 Stainless steel (SUS304/316L): Used in environments that may have chemical corrosivity or higher humidity, or for electronic workshops with special requirements (such as chip manufacturing).
4. Static pressure box and air distribution device
4.1 The static pressure box should have a reasonable guide design to ensure uniform airflow through the filter cross-section and avoid dead angles.
4.2 Air distribution membrane/perforated plate: The function is to make the outlet airflow more uniform and stable, avoiding vortex and turbulence. Different opening rates can be chosen according to the required airspeed.
5. Air volume and resistance
5.1 Determine the air volume for each air outlet based on the air exchange rate calculated for the designed cleanliness level. When selecting the model, the actual operating air volume should not exceed the rated air volume.
5.2 When calculating the total resistance of the system, the initial resistance and final resistance (usually twice the initial resistance) of the high-efficiency air outlet must be included to correctly select the central air conditioning fan.
6. Measurement holes and DOP ports
Standard air outlets should have reserved pressure difference measurement holes for installing pressure difference meters to monitor filter blockage. PAO/DOP smoke ports should be reserved for regular on-site scanning and leak detection, which is core work for maintaining clean room performance.
In summary, in electronic clean rooms, integrated high-efficiency air outlets are an efficient, reliable, and cost-effective solution for constructing ISO Class 6 (1,000 level) and lower cleanliness environments. The core of its technical application lies in: providing clean air through high-efficiency filtration; ensuring airflow quality and zero leakage through liquid seal and air distribution design; achieving convenient installation and maintenance through modular design.
Correctly selecting and installing integrated high-efficiency air outlets, along with a strict leak detection and maintenance system, is the foundation for ensuring the cleanliness of electronic workshops and improving product yield.
