What should I do if the FFU inlet air interferes with each other after expansion? Shared mezzanine and clearance inspection
Why does air inlet interference occur after expansion?
When the clean room is expanded, the number of FFUs is often increased in the original suspended ceiling mezzanine. In the initial stage of capacity expansion, the test of a single FFU may be normal, but after running for a period of time, it is found that the air volume of some FFUs decreases or fluctuates, and even the wind speeds of FFUs in the same area are inconsistent.
This situation may not be a problem with the FFU itself, but a change in the air inlet conditions of the shared mezzanine. FFU needs to suck air from the mezzanine, filter it and send it to the clean room. If the mezzanine space is insufficient or the air inlet path is blocked, multiple FFUs may compete for air with each other when running at the same time, causing air inlet interference.
The manifestations of air inlet interference include: the air volume of some FFUs decreases, the air inlet of some FFUs is uneven, the fan speed increases but the air volume does not increase, the noise increases, and even airflow backflow occurs. If the capacity expansion project only increases the number of FFU without simultaneously evaluating the mezzanine air inlet conditions, these problems may occur. Aili Industrial has complete production capabilities in FFU complete machines and transformation supporting equipment, and can cooperate with the project to check the air inlet conditions after the expansion. For the basic structure of the FFU machine, please refer toAili Industrial FFU fan filter unit。
What should I check for mezzanine clearance?
Mezzanine clearance is the basic condition for FFU air intake. The inspection contents include: the distance from the FFU air inlet to the top of the mezzanine or the bottom of the structure; whether there are bridges, pipelines, lamps or structures blocking the air inlet; whether the spacing between multiple FFUs is sufficient; whether there are partitions or obstacles in the mezzanine that affect the air flow.
If the FFU air inlet is too close to the top of the mezzanine, the air inlet resistance will increase. If there are bridges or pipelines around the air inlet, local air intake may be uneven. If multiple FFUs are arranged side by side with a small distance, adjacent FFUs may compete for air in the same area.
It is recommended to use drawings and on-site actual measurements for clearance inspection. Drawings can confirm the design dimensions, and on-site measurements can confirm the clearance after actual installation. For expansion projects, pipelines and other equipment may have been arranged in the original mezzanine, and the clearance after adding the FFU needs to be re-confirmed.
How to evaluate the air supply of a shared mezzanine
The air supply to the shared mezzanine comes from return air, fresh air or adjacent areas. After the expansion, the total air volume of FFU increases, and the mezzanine needs to provide more air. If the supply path is not increased accordingly, negative pressure may form in the mezzanine, affecting the FFU air intake.
When evaluating the air supply, you can check the following: whether the connection between the mezzanine and the return air channel is smooth; whether the area of the return air outlet between the mezzanine and the clean room is sufficient; whether the location and air volume of the fresh air supply into the mezzanine are appropriate; whether there is local negative pressure or dead air flow in the mezzanine; whether the air distribution is even when multiple areas share the mezzanine.
If the mezzanine supply is insufficient, you can consider adding return air outlets, adjusting the fresh air supply position, or optimizing the mezzanine partition. For capacity expansion projects, it is recommended to calculate the mezzanine air supply capacity while increasing FFU.
How to check the air inlet path
The air inlet path inspection can be confirmed step by step from the mezzanine entrance to the FFU air inlet. Confirm the direction from which the air enters the mezzanine, whether the path is smooth, and whether there is any local necking or obstruction. Confirm the air flow direction around the FFU air inlet to see if there is backflow or vortex. Check whether the airflow between multiple FFUs interferes with each other.
During the inspection, you can use an anemometer to measure the wind speed at different locations in the mezzanine, or use a smoke device to observe the direction of the air flow. If you find that the air intake of a certain FFU is obviously weak, you can check the clearance and occlusion above and around it.
For expansion projects, the air inlet path of the original FFU may change due to new equipment. It is recommended to record the air inlet status before and after expansion for easy comparison.
What are the directions for adjustment?
If the incoming wind interference is confirmed, it can be adjusted in several directions. Increase the mezzanine clearance and remove the bridge or pipeline above the FFU air inlet. Adjust FFU layout, increase equipment spacing or change arrangement. Increase the mezzanine air supply, such as adding return air vents or adjusting fresh air supply. Optimize mezzanine partitions to avoid interference between different areas. Adjust the FFU speed or control method to reduce local air intake competition.
When adjusting, it is necessary to simultaneously confirm whether the FFU air volume, static pressure and noise have returned to normal. If interference persists after adjustments, the mezzanine design and FFU placement may need to be re-evaluated. For projects that require group control, partition settings can be used to reduce the mutual influence of different areas. For details, please refer toFFU/EFU group control touch screen controller andFFU computer group control system。
Checks to be made before capacity expansion
In order to avoid air inlet interference after expansion, it is recommended to make the following checks before expansion. Confirm the existing clearance and occupancy of the mezzanine; confirm the total air volume and mezzanine supply capacity after the addition of FFU; confirm the layout and spacing of FFU; confirm whether the air inlet path is affected by the new equipment; confirm whether the return air outlet and fresh air supply meet the post-expansion requirements; confirm whether the mezzanine partitions or pipelines need to be adjusted.
For expansion projects with limited space, you can consider using ultra-thin FFU or small-size FFU to reduce the impact on the mezzanine clearance. For specific structure, please refer toUltra-thin FFU and70mm ultra-thin EFU。
Issues that should be confirmed in advance during project communication
During the design and implementation stage of the FFU capacity expansion project, it is recommended to confirm the following with the manufacturer and designer: the existing clearance and occupancy of the mezzanine; the number and total air volume of new FFU; the air supply capacity of the mezzanine; the air inlet path and occlusion; the layout and spacing of FFU; the position of the return air outlet and fresh air supply; whether the mezzanine partition needs to be adjusted; debugging and verification methods.
If you are planning an FFU expansion project, you can visitAili Industrial FFU fan filter unit understands the complete machine configuration, and you can also contact Aili Industrial to obtain support for expansion solutions.
in conclusion
Air inlet interference after FFU expansion usually comes from insufficient clearance in the shared mezzanine, insufficient air supply, or the air inlet path is blocked. When troubleshooting, you should check the mezzanine clearance, air supply and air inlet path, instead of just increasing the speed one by one. Adjustments include increasing headroom, adjusting layout, adding supplies, and optimizing partitioning.
Aili Industrial has complete production capabilities in FFU complete machines and transformation supporting equipment, and can cooperate with the project to check the air inlet conditions after the expansion. If you need to know more about the FFU expansion plan, you can visitAili Industrial FFU fan filter unit , you are also welcome to contact Aili Industrial for project support.
