What is the reason why ULPA is qualified before leaving the factory but air leaks on site? Transportation and installation damage inspection

If the ULPA factory leakage test is qualified but the air leaks on site, it needs to be traced layer by layer along the transportation, unpacking, assembly and on-site testing conditions. The factory inspection verified the condition of the filter element at that time, and the sealing interface between the box and the installation was also added on site. Air leakage does not mean that the filter element itself is unqualified, nor does it mean that the factory report is invalid. The key is to distinguish the main problem from the system bypass. Aili Industrial has corresponding capabilities in filter manufacturing, sheet metal processing and complete machine assembly, and can help separate these two types of causes during the investigation stage.

1. Preserve abnormal evidence first, and then talk about the reasons

Record the filter element number, packaging damage location, installation point and leak point coordinates, and compare the objects reported at the factory and on-site to see if they are consistent. Do not remove the filter element first and then take another photo to avoid losing the assembly status information.

With a complete chain of evidence, it can only be determined later whether it is a transportation stress, installation compression, or sealing interface problem. The relationship between levels and particle limits can be found inISO cleanliness level comparison。

2. Distinguish the cause direction according to the location of air leakage

If there are local abnormalities on the filter surface, check for accidental collision and media damage; if there are continuous abnormalities along the entire edge, check the gasket compression, knife-edge fit, and box flatness. Corner air leakage may also involve both glue joints and installation bypasses.

Different positions correspond to different processing paths. Positioning first and then disassembly and assembly is more effective than total replacement. Please refer to the key points of ULPA sealing and leak detection.ULPA ultra-high efficiency filter FAQ and selection guide。

3. Common injuries during transportation and unpacking

Large-size ULPA may cause frame deformation and glue seam damage during transportation due to insufficient support, stacking pressure, or turning and collision. When unpacking, the cutter scratches the filter surface and packaging debris enters the sealing surface, which will also cause air leakage after installation.

Aili Industrial can provide packaging and handling requirements during the filter delivery process. Large-size models are designed with supports based on the allowable stress positions of the frame to reduce the risk of transportation deformation. Customized models on the device side can also be combined withthe fan filter unit on the EFU equipment side .Confirm the unpacking and installation sequence of the installation interface of

4. Sealing interface issues in the assembly process

During installation, gasket curling, uneven pressing force, insufficient liquid level in the liquid tank, or uneven box joints will prevent the sealing surface from being able to fit continuously. This type of problem cannot be seen during factory inspection and can only be discovered by leak detection after installation.

Aili Industry can combine filter manufacturing, sheet metal and complete machine assembly to check the filter frame, box and sealing interface; ceiling scenarios can be matchedConfirm the installation structure of the FFU fan filter unit . Please refer to the matching of sealing method and leak detection method.HEPA FAQs and Selection Guide。

5. On-site test conditions must also be reviewed

The aerosol, test air volume and instrument status are different from the factory conditions, which may also cause differences in results. Insufficient upstream concentration, contamination of the sampling pipeline, or high background may cause local signal abnormalities.

When reviewing, you should first confirm that the test conditions are valid before judging product problems. Please refer to the ULPA leak detection method and threshold determination.ULPA ultra-high efficiency filter FAQ and selection guide。

6. Related questions and answers

Can the factory report still be used?
Can. The factory report is used to trace the testing status after manufacturing. On-site acceptance should still be judged based on the actual assembly results. The two cannot replace each other.

What does it mean if the air leakage disappears after the same filter element is re-tightened?
This shows that the installation factors are worth continuing to check, but it cannot be concluded that there are no problems with the same batch of filter elements. The processing results should be recorded separately by batch and point.

The air leakage is at the corner. Should I check the glue joint or seal it first?
The corners may involve both glue seams and installation bypasses. You should first check the relative positions of the leakage point and the sealing surface, and then check them separately. It is not advisable to directly disassemble the filter element.

7. Related articles

ULPA ultra-high efficiency filter FAQ and selection guide

HEPA FAQs and Selection Guide

EFU FAQ and technical support

ISO cleanliness level comparison

8. Key points for selection and acceptance inspection

9. Product matching and technical support from Aili Industrial

Aili Industrial can check the filter frame, box and sealing interface in combination with filter manufacturing, sheet metal and complete machine assembly. Providing the location of leaks, working conditions and installation diagrams during project communication will help separate ontology issues and system bypasses. ULPA products can be viewedHEPA/ULPA filter page; equipment-side items can be checked at the same timeEFU equipment end fan filter unit ; clean area projects can be combinedFFU fan filter unit discussion. Provide process objectives, installation drawings, operating conditions and acceptance requirements, and can further communicate ULPA standard specifications, non-standard interfaces, samples and batch matching. The specific parameters and test range are based on the confirmed model and technical documents.