How to customize side air intake EFU? Air inlet position, air duct resistance and equipment interface confirmation

Direct answer: The core of the customization of side air inlet EFU is not to select a standard product first and then change the interface, but to determine the structure inversely from the available space inside the equipment, air inlet direction, air duct resistance and equipment interface conditions. It is necessary to first confirm whether the position of the air inlet is blocked by mechanical structures, pipes or cables, then evaluate the additional resistance brought by the side air inlet path, and finally determine the fan working point, box size and installation interface.

For applications with limited internal space such as semiconductor equipment, placement machines, and precision testing equipment, side air intake is often a last resort but necessary choice. Understanding the differences between side-inlet EFU and conventional top-inlet EFU is the prerequisite for the success of a customized solution.

1. Why does the equipment-side EFU adopt a side air inlet structure?

Conventional EFU mostly adopts a structure with air inlet from the top and air outlet from the bottom. The air path is direct and the resistance is small. However, inside the equipment, the top space is often occupied by mechanical modules, cable trays or safety covers, making it impossible to reserve air inlet space.

The structural characteristics of the side-intake EFU are that the air enters from the side of the box, is accelerated by the fan, passes through the high-efficiency filter, and is then sent from the air outlet surface into the target clean area. This structure is more suitable for the following scenarios:

• The top of the equipment is blocked by a mechanical structure or safety cover;

• The EFU needs to be embedded into the side wall or lateral bracket of the device;

• The airflow organization inside the equipment requires lateral supplementary air;

• The maintenance space is only accessible from the side of the equipment.

If you are selecting a model for the device, you can first refer toThe overall product system of the equipment-end fan filter unit (EFU) is then determined whether a side air inlet structure is needed.

2. How to determine the position of the air inlet? Look at the occlusion first, then the airflow

The position of the air inlet of the side air inlet EFU cannot be determined arbitrarily and needs to be confirmed one by one based on the internal structure of the equipment:

1. Mechanical movement range : Whether the air inlet is on the movement path of the mechanical arm, transmission mechanism or mobile module;

2. Pipes and cables : Whether air pipes, liquid pipes, and cable bridges will block the air inlet surface;

3. Adjacent components : Are there any heating elements or dust-generating components opposite the air inlet?

4. Maintenance channel : Whether filter replacement and fan maintenance need to be done from the air inlet side;

5. Return air path : After side air intake, whether the return air inside the equipment can form a reasonable circulation to avoid short circuit.

Once the position of the air inlet is determined, the box structure, fan installation direction and filter orientation will also be determined. This is why side-inlet EFU usually requires non-standard design based on equipment drawings, rather than directly selecting standard products.

For applications where space is particularly tight, you can refer tothe fan filter unit of the small-sized EFU equipment is combined with the design of the side air inlet interface.The compact structure of

3. What air duct resistance will the side air intake bring?

Compared with the straight air inlet from the top, the air path of the side air inlet structure is more tortuous, which usually increases the following resistance:

• Local resistance of the air inlet : lateral opening area, flow guide fillet, grille or protective net will all affect the air intake efficiency;

• Turning resistance inside the box : Eddy current loss occurs when the airflow turns from side to axial or vertical direction;

• Uniformity of the front section of the filter : Side air inlet can easily cause uneven wind speed on the windward side of the filter;

• Fan operating point shift : After the resistance increases, the air volume of the same fan in the actual system will be lower than the nominal value.

Therefore, the side air inlet EFU cannot only look at the nominal air volume of the fan, but should be combined with the system resistance curve to confirm the actual operating point. If necessary, wind speed uniformity can be evaluated through CFD simulation or prototype testing.

If the project has requirements for energy consumption and speed regulation, considerThe DC EFU equipment fan filter unit solution uses the EC/DC fan to maintain adjustable operation when the resistance changes.

4. Equipment interface confirmation: size, sealing, fixing and tolerances

The interface confirmation of the side-inlet EFU is usually more complicated than the standard EFU. During the design stage, you need to confirm the following with the equipment manufacturer:

The earlier the interface is confirmed, the less subsequent prototype rework will be. For stainless steel or equipment with higher cleanliness requirements, please refer tosnap-on EFU .The filter fixation and box structure ideas of

5. How to match the filter and fan of the side inlet EFU?

After the side air inlet structure is determined, the matching of the filter and the fan needs to be carried out simultaneously:

• Filter grade : Choose HEPA H13/H14 or ULPA U15/U16 according to cleanliness requirements;

• Filter size : needs to match the internal space of the side air inlet box to avoid compression of the diffusion distance;

• Fan type : Choose EC, DC or AC fan according to air volume, static pressure and speed regulation requirements;

• Number of fans : single or multiple configurations, affecting wind speed uniformity and noise;

• Control method : Whether it needs to be linked with the equipment PLC, RS485/Modbus communication or group control.

For projects with a small number of equipment and requiring on-site centralized control, we can cooperate withThe small FFU/EFU controller realizes start and stop, speed adjustment and communication status viewing.

6. Customization direction of side air inlet EFU in different equipment scenarios

The customization requirements for side air inlet EFU are often closely related to the type of equipment:

• Semiconductor equipment : compact space, high cleanliness requirements, and often need to be linked with the equipment main control;

• SMT placement machine : The top safety cover space is limited, please refer toFFU/EFU dedicated to SMT placement machines ;Adaptation ideas for

• Static Sensitive Devices : ConfigurableAnti-static EFU , taking into account both cleanliness and static electricity control;

• Ultra-thin installation scenario : when the height of the equipment is limited, please refer toThe structural direction of the ultra-thin EFU ;

• In-depth non-standard projects : please refer toThe overall customization process of customizing the fan filter unit at the EFU equipment end .

7. What information do I need to provide for side-inlet EFU customization?

In order to improve the efficiency of plan confirmation, it is recommended to provide:

1. Available length, width and height inside the device;

2. Available locations and sizes of side air inlets;

3. Target air supply area and allowable wind speed;

4. Air duct resistance or static pressure requirements;

5. Filtration efficiency and filter size;

6. Power supply, control methods and communication requirements;

7. Equipment drawings or installation interface sketches;

8. Estimated quantity and delivery date.

In non-standard EFU projects, Aili Industrial will first confirm the equipment boundaries and acceptance conditions, and then match the fans, motors, filters, boxes and control systems. For side air intake, ultra-thin or special interface solutions, the curing drawings, materials and control parameters can be tested through the prototype and the first one, so that subsequent batches can maintain consistent configurations.

FAQ

What is the difference between side-inlet EFU and top-inlet EFU?

The air of the side-inlet EFU enters from the side of the box, which is suitable for equipment with limited top space; the top-inlet EFU has a more conventional structure and relatively small resistance. Which structure to choose depends on the internal space and airflow organization requirements of the equipment.

Will the air volume of the side-intake EFU be lower than that of the top-intake EFU?

Under other conditions being equal, the resistance of the side air inlet path is usually higher, and the actual air volume may be lower than the top air inlet solution. Specific differences need to be evaluated in combination with fan performance, box structure and filter resistance.

Can the side-inlet EFU be customized with a stainless steel box?

Can. SUS304, SUS316 and other stainless steel boxes can be configured according to project requirements, and are suitable for equipment environments with high requirements for cleanliness and corrosion resistance.

Can side air inlet EFU be equipped with anti-static function?

Can. For static-sensitive equipment, an anti-static module can be configured to take into account both clean air supply and static electricity control.

How to replace the side air inlet EFU filter?

The method of filter replacement depends on the box structure. Some solutions can be disassembled and assembled from the side or bottom, and the specific needs are determined at the design stage based on the equipment maintenance space.

Can the side-inlet EFU be accepted using simulation results?

Simulation can assist the design, but the final measurement should be confirmed according to the agreed working conditions, including the measurement plane, the number of measurement points, and the wind volume or wind speed judgment value.