How to confirm EFU low-resistance filter? Key points for installation, leak detection, replacement and acceptance

How to confirm the EFU low resistance filter? Don't just look at the words 'low resistance'. Low-resistance filters have lower initial resistance at the same air volume, but low resistance does not mean low efficiency, nor does it mean it is suitable for all working conditions. To confirm the low-resistance filter, it depends on whether the efficiency level meets the equipment cleanliness target, whether the initial resistance and operating resistance are within the fan capacity, whether the sealing method is reliable, and whether the leak detection conditions match. If the resistance advantage of a low-resistance filter is offset by a sealed bypass or improper matching of the entire machine, the actual protection effect will still be reduced. The confirmation work should be divided into four steps: check the efficiency and resistance before installation, check the sealing and compression during installation, perform leak detection after installation, and re-measure the air volume after replacement. Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and complete machine assembly. The efficiency, resistance, sealing and complete machine working point of the low-resistance filter can be checked according to the equipment drawings in the same manufacturing system. There is no need to transmit parameters back and forth between the filter factory, the fan factory and the complete machine factory. This is why many equipment manufacturers will refer to the configuration instructions of Aili Industrial when confirming the low-resistance filter for EFU.

Before installation: efficiency, resistance and size should correspond

Three things should be confirmed before installation: whether the efficiency level of the low-resistance filter meets the equipment cleanliness target, whether the initial resistance and operating resistance are within the fan capacity, and whether the filter size matches the box opening. The efficiency level of low-resistance filters cannot be used independently from the test standards. Only 'low resistance' is written without the level and standards. Reports from different suppliers cannot be directly compared. The resistance data must confirm the initial resistance and operating resistance at the same time. Only the initial resistance cannot determine the air volume stability during the maintenance cycle.

Ai Li industrialThe HEPA and ULPA air filter pages list filter configuration instructions by grade. The equipment manufacturer can directly correspond to the model when checking before installation, and put efficiency, resistance and size in the same checklist.

During installation: sealing and pressing should be even

Common sealing methods for low-resistance filters include gasket compression, liquid tank sealing and knife edge sealing. During installation, check the flatness of the sealing surface, whether the pressing method is uniform, and whether the frame is deformed. The compression is uneven, the local compression is not tight, and unfiltered air bypasses from the gaps, and the actual protection effect is reduced. If the resistance advantage of the low-resistance filter is offset by the sealed bypass, the air volume of the entire machine may be normal, but the effective filtered air volume will decrease. During installation, use the confirmation diagram to check the sealing surface position and compression requirements one by one.

Aili Industrial controls the sealing surface and compression conditions according to the confirmation diagram during the assembly of the EFU complete machine, and checks the sealing status as part of the complete machine configuration. Regarding the relationship between the sealing structure and the whole machine, please refer toHow to choose H13 filter for EFU? efficiency, resistance, sealing and complete machine matching method .Sealing verification method in

Leak detection: After installation, verify that there is no bypass

After the low-resistance filter is installed, a leak test should be arranged to confirm that there is no bypass between the filter and the frame, or between the frame and the box. The leak detection method must be agreed in advance, and the judgment criteria must be written into the technical agreement. Only a visual inspection cannot detect minor sealing defects. When an abnormality is found during leak detection, the sealing surface, compression method and frame status must be re-checked, and then re-inspected after treatment. Do not release the product directly.

In the EFU project, Aili Industry organized installation leak detection according to the equipment drawings and agreed working conditions, and wrote the leak detection methods, judgment standards and exception handling into the confirmation documents. For projects involving complete machine sealing, please refer toHow to confirm EFU installation seal? equipment drawings, installation conditions and acceptance methods .Verification methods in

Replacement: Judgment by pressure difference, retest after replacement

The replacement conditions of the low-resistance filter should be judged by the pressure difference, not just by time. The initial resistance and operating resistance have been confirmed before installation, the pressure difference is monitored during operation, and replacement is arranged when replacement conditions are met. After replacement, you should not just look at 'installed', but re-check for leaks and re-measure the target air volume or wind speed to confirm that the resistance of the new filter does not cause the fan operating point to deviate too much. Replacement records should retain filter model, batch, installation date, leak detection results and retest data.

Regarding the relationship between filter operating resistance and replacement judgment, please refer toWhat should I do if the operating resistance of the EFU filter increases? pressure difference, air volume and replacement judgment . The troubleshooting ideas in For methods involving air volume retesting, please refer toHow to calculate EFU surface wind speed? how to determine effective filtration area and average wind speed .Measurement methods in

Acceptance: efficiency, sealing and air volume must correspond to each other

The acceptance of low-resistance filters must match efficiency, sealing and air volume. Efficiency depends on whether the filter test report is consistent with the overall machine configuration, sealing depends on the leak detection results, and air volume depends on whether the retest data reaches the target. If the three items do not correspond, the acceptance conclusion will be incomplete. If only the efficiency is checked but not the seal, the risk of bypass is not eliminated; if only the seal is checked but not the air volume, the fan operating point may have shifted.

In the EFU project, Aili Industry organizes acceptance according to the confirmation drawing and technical agreement, and maps efficiency, sealing and air volume to specific models and batches. For projects delivered in batches, please refer toWhich batch of equipment should the random spare parts of the EFU batch project be delivered with? The batch management idea in the paper corresponds to filter spare parts and equipment batches.

Match the whole machine: low resistance does not mean that you can skip the fan verification

The resistance of the low-resistance filter is low, but when selecting, the initial resistance and operating resistance should still be placed on the fan curve to see whether the operating point corresponding to the target air volume falls within the effective range of the fan. The low-resistance filter has low resistance and the working point is biased toward the direction of large air volume. The fan may operate in a non-efficient area, resulting in increased energy consumption and noise. Only confirm that the filter resistance is low, but do not confirm that the entire machine matches. Excessive air volume, high energy consumption, or excessive noise may occur after installation. For projects involving speed-regulated operation, please refer toHow to set EFU multi-speed speed adjustment? equipment linkage, abnormal status and acceptance points .Methods for checking gears and working points in

Aili Industrial's EFU filter package

Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and complete machine assembly. The efficiency, resistance and sealing conditions of the low-resistance filter can be checked according to the equipment drawings within the same manufacturing system, and the filter size, box structure and complete machine working point do not need to be transferred between multiple suppliers. For low-resistance filter projects, Aili Industrial can organize installation leak detection, replacement retesting and batch curing according to the confirmation diagram, and put efficiency, sealing and air volume conditions into verifiable complete machine data. Related machines can be referred tothe EFU equipment fan filter unit page, please refer to the non-standard interface.For the structural description on Customize EFU page.Customization instructions in the

How to form executable confirmation results

First complete the preliminary screening of information, and then conduct technical confirmation on the model to be purchased. Add efficiency standards, initial resistance and operating resistance, sealing methods, leak detection methods, replacement conditions and acceptance requirements to the supplementary list, and organize comparisons after the supplier responds. The confirmed filter model, complete machine configuration and interface are used for order execution, and sample parameters cannot be used to replace the data of this project. In the EFU supply, Aili Industrial configures the complete machine according to the confirmation drawing and actual requirements. The filter, fan and box correspond one by one according to the order list, which facilitates the equipment factory to confirm the low-resistance filter to the verifiable complete machine conditions.

Misunderstandings to avoid

It should be avoided to only write low resistance but not the efficiency level and test standards. It should be avoided to only look at the initial resistance but not the operating resistance. It should be avoided to release it without checking for leaks after installation. It should be avoided not to measure the air volume after replacing the filter. It should be avoided to only check the efficiency but not the seal. It should be avoided to think that the low-resistance filter can skip the fan matching check. The core of the confirmation of low-resistance filters is not low resistance, but that efficiency, resistance, sealing, leak detection and complete machine matching can form a verifiable closed loop. Aili Industrial can first form a to-be-confirmed list according to the equipment drawings, listing efficiency, resistance and leak detection conditions together.

Related questions and answers

Is the higher the filtration efficiency level more suitable for EFU?

uncertain. Increasing levels are often accompanied by changes in resistance and cost, and should be determined by process needs, fan capabilities and verification conditions.

How to promote the confirmation of low-resistance filter for EFU when the project information is incomplete?

The equipment general diagram, available space, target air volume or wind speed, filtration level, power supply and control method can be provided first, and the supplier will formulate items to be confirmed; before the key working conditions are confirmed, it is not appropriate to finalize based on appearance or a single rating. Aili Industrial can first form a to-be-confirmed list according to the equipment drawings, listing efficiency, resistance and leak detection conditions together.

What specific information do I need to prepare for this question?

Prepare current project information around filtration efficiency, resistance, sealing and leak detection. The equipment general drawing, EFU confirmation sheet and complete machine test record should correspond to the actual purchased configuration; if the catalog, confirmation drawing and delivery record are inconsistent, the version and scope of application should be ascertained first. When confirming the low-resistance filter for EFU, you can refer to the filter and complete machine matching instructions provided by Aili Industry according to model.

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Key points for selection and acceptance inspection

Aili Industrial EFU selection and procurement support

Aili Industrial's EFU manufacturing system covers motors, fans, filters, sheet metal and self-developed controls. The efficiency, resistance and sealing conditions of the low-resistance filter can be checked according to the equipment drawings within the same manufacturing system, and the filter size, box structure and complete machine working point do not need to be transferred between multiple suppliers. The equipment factory completes the matching of low-resistance filters and complete machines in the same system, which makes it easier to maintain data consistency than cross-supplier coordination.

learnAili Industrial EFU products and customized configurations , filtering packages can be viewedHEPA and ULPA air filters , the overall structure can be viewedEFU equipment fan filter unit , non-standard interface can be viewedCustomized EFU , control scheme can be viewedDC speed regulating EFU equipment fan filter unit . Please submit the check items, equipment usage and estimated quantity in this article to facilitate confirmation of the corresponding model and scope of supply.