What should I do if ULPA cannot be installed due to size deviation? Drawing and physical review

When the size deviation of the ULPA filter makes it impossible to install, the forced assembly should be suspended and the drawing version, measurement benchmark and actual installation port should be checked. First determine whether it is a problem with the filter element, equipment interface, or tolerance superposition, and then determine the solution. Forced installation will often deform the outer frame or damage the sealing surface, turning dimensional problems that could have been corrected into scrapping the entire piece. Aili Industrial's approach to dealing with such problems is to first use drawing versions and bilateral measured data to locate deviations in specific links, and then provide rectification plans instead of repeated trial installations on site.

1. Check the same set of definitions: first confirm whether both parties are talking about the same size.

Confirm whether nominal dimensions, outer frame dimensions and dimensions including seals are mixed, and check the direction and drawing version. Deformation of old parts may also cause deviations in surveying and mapping.

Disputes over size deviations are often not about who made the mistake, but rather that the two parties measured the sizes of different calibers. Aili Industry isIn the non-standard ULPA filter project, the version record of the confirmation drawing and the measurement reference description of the key dimensions will be kept. When a deviation occurs, you can quickly check whether it is a version problem, a caliber problem or an actual processing deviation, instead of repeatedly guessing on site. For the definition of size and diameter, please refer toHEPA FAQs and Selection Guide。

2. Retest the interfaces on both sides separately: Don't just say 'the size is wrong'

Record the shape, openings, support steps and sealing surface of the filter element, and mark the interference location. Don't just say 'wrong size' without missing measurements.

The key to deviation positioning is to record the actual measured data on the filter element side and the installation port side separately. Aili Industrial has bothWith HEPA/ULPA filter frame processing and sheet metal box matching capabilities, the processing data of the filter element side and the box side can be retrieved in the same system, and compared with on-site measurements in three ways to determine whether the deviation comes from the filter element, the box, or the extreme combination of the two. This comparison is often difficult to complete if both sides belong to different suppliers. Please refer to the key points for retesting the internal installation port of the equipment.the fan filter unit on the EFU equipment side .Instructions related to

3. If one side can be loaded and the other side is stuck, check the squareness first.

When one side can fit in and the other side is stuck, the squareness and diagonal should be checked. Do not just reduce the size of the long side of the outer frame. Diagonal misalignment will cause the filter element to interfere locally on one side, while the long side dimensions will look completely normal.

This kind of deviation cannot be seen in unilateral measurement, and the diagonal must be measured. Aili Industry isnon-standard ULPA filters will be checked before leaving the factory. When on-site interference occurs, it can be judged whether it is transportation deformation or processing deviation. The diagonal or squareness of The matching dimensions for ceiling installation can be combinedCheck the box interface of the FFU fan filter unit .

4. Make rectifications according to the approved plan and do not repair the filter frame without authorization

Changes involving cutting, bending or sealing interfaces should first assess the structural and integrity impacts. After rectification, recheck the assembly and leak detection requirements. On-site grinding of the filter frame may affect the sealing and media, and the prescribed plan should be adopted after evaluation and confirmation.

Aili Industry isFor non-standard ULPA filter projects, samples can be pre-assembled first to expose dimensional interference before mass production and reduce the probability of on-site rectification. When rectification is really needed, solutions can be given from both sides of the filter frame and box, rather than just one side. The relationship between sealing surface and structural rectification can be referred toULPA ultra-high efficiency filter FAQ and selection guide。

5. Related questions and answers

Can the filter frame be repaired on site?
It is not advisable to operate without authorization. Grinding may affect the seal and medium, and the prescribed plan should be adopted after evaluation and confirmation.

One side can be loaded and the other side is stuck, why?
Common causes are diagonal deviation or box squareness issues. Measure diagonally, not just the long side.

Is dimensional deviation necessarily a manufacturing issue?
uncertain. It may also be caused by inconsistent measurement calibers, different drawing versions, or superimposed tolerances. The actual measured data on the filter element side and the installation port side should be checked separately.

6. 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

7. Key points for selection and acceptance inspection

8. Product matching and technical support from Aili Industrial

Aili Industry isThe non-standard ULPA filter project keeps the version record of the confirmed drawings and the measurement reference instructions. When there is a dimensional deviation, it can be quickly determined whether it is a version, caliber or processing problem. The filter frame and sheet metal box are completed in the same manufacturing system.The processing data on the HEPA/ULPA filter side and the box side can be compared with actual on-site measurements in three ways to locate the source of the deviation. The project can be based on the sample pre-assembly mechanism to expose dimensional interference before mass production, reducing on-site rectification. Ceiling projects can be combinedFFU fan filter unit checks matching dimensions, and equipment-side items can be checked at the same timeEFU equipment side fan filter unit . Provide process objectives, installation drawings, operating conditions and acceptance requirements for further communicationULPA ultra-high efficiency filters . Standard specifications, non-standard interfaces, samples and batch matching of The specific parameters and test range are based on the confirmed model and technical documents.