How to write filter replacement conditions and maintenance scope in FFU technical agreement
Why can’t you just write how many months it has been used?
In the FFU technical agreement, the filter replacement conditions are sometimes simply written as the number of months of use before replacement. This way of writing seems clear, but may not be applicable in actual operation.
Filter life is affected by inlet pollution load, operating time, air volume, filter dust holding capacity and process environment. In different areas and under different working conditions, the actual life of the filter may vary greatly. If they are replaced at the same time, it may be blocked before expiration, or it may continue to be used after expiration.
Therefore, the filter replacement conditions should be agreed in combination with resistance, air volume, integrity and process requirements, rather than just writing the time. The scope of maintenance should also describe the responsibilities for structural disassembly, retesting, and consumables. Aili Industrial has complete production capabilities in FFU complete machines and filters, and can cooperate with the project to formulate replacement and maintenance conditions. For the basic structure of the FFU machine, please refer toAili Industrial FFU fan filter unit。
How to agree on resistance conditions
Resistance conditions are a common basis for filter replacement. After the filter accumulates dust, the resistance increases. When the resistance reaches the set value, it means that the filter needs to be replaced or maintained.
The resistance condition can be agreed as: the filter resistance reaches a certain multiple of the initial resistance, or reaches a certain absolute value. Specific values should be determined based on filter type and system conditions. If the project has differential pressure monitoring, it can be judged based on the differential pressure reading. If there is no monitoring, it can be measured periodically.
The resistance conditions should describe the measurement location and method to ensure consistent judgment.
How to agree on air volume conditions
The air volume condition is also the basis for judging replacement. After the filter resistance increases, if the FFU adopts constant speed control, the air volume will decrease. When the air volume is lower than the set value, the filter needs to be replaced.
The air volume condition can be agreed as: the air volume is lower than a certain percentage of the initial air volume, or lower than the minimum air volume required by the process. Air volume measurement should be carried out under agreed working conditions.
For constant air volume control, the air volume can be maintained, but the fan power or speed will increase. At this time, it can be judged based on changes in power or speed.
How to agree on integrity conditions
Filter integrity is another condition for replacement. If the filter fails to detect leaks, the filter material is damaged, or the seal fails, it needs to be replaced. Integrity conditions can be agreed as follows: leak detection fails; visible damage to filter material; damaged sealing surface; irrecoverable from moisture or contamination.
Integrity checks are usually performed during regular maintenance or troubleshooting. If integrity problems are found, they should be dealt with promptly.
How to agree on process requirements
Process requirements may also affect replacement conditions. If the cleanliness test does not meet the standard and the investigation confirms that it is related to the filter, it may need to be replaced. Filters may also need to be inspected if there is an increase in product defects associated with particle contamination.
Process requirements should be judged in conjunction with filter status, rather than alone as a basis for replacement.
How to write maintenance scope
The maintenance scope should make it clear who is responsible for what work. Content includes: daily inspection; resistance or air volume recording; filter replacement; seal inspection; leak detection; electrical inspection; controller maintenance; and supply of consumables.
The maintenance scope should also describe the disassembly structure, such as top-up or bottom-down type, and the space and tools required for maintenance. If maintenance requires downtime or affects production, how it will be arranged should be explained.
How to agree on consumables responsibility
Responsibility for consumables should specify who supplies filters, sealing strips, spare parts, etc. and how the costs are borne. If the filter is damaged due to quality problems during the warranty period, how is the responsibility divided? How is responsibility divided if operating conditions lead to premature replacement?
Responsibilities for consumables should be clearly stated in the technical agreement to avoid later disputes.
How to agree on data update
After the filter is replaced, the relevant records should be updated. Includes replacement date, filter batch, leak detection results and operating status. If the FFU configuration version changes, the data should also be updated.
Responsibilities for updating data should be clearly defined to ensure complete maintenance of records.
Issues that should be confirmed in advance during project communication
During the formulation stage of the FFU technical agreement, it is recommended to confirm the following contents with the manufacturer: filter replacement judgment conditions; resistance or air volume measurement methods; integrity inspection methods; maintenance scope and responsibilities; consumable supplies and costs; replacement structures and spaces; leak detection and retest requirements; and data update requirements.
If you are developing an FFU technical agreement, you can visitAili Industrial FFU fan filter unit to learn about the complete machine configuration, you can also refer toFFU supports ULPA ultra-high efficiency filters to learn about filter products, or contact Aili Industrial for technical agreement support.
in conclusion
In the FFU technical agreement, the filter replacement conditions should be agreed based on resistance, air volume, integrity and process requirements, rather than uniformly written in the number of months of use. The scope of maintenance should describe the responsibilities for dismantling structures, retesting and consumables. Judgment conditions, maintenance responsibilities and data updates should be specified in the agreement.
Aili Industrial has complete production capabilities in FFU complete machines and filters, and can cooperate with the project to formulate replacement and maintenance conditions. If you need to know more about the FFU technical agreement, you can visitAili Industrial FFU fan filter unit , you are also welcome to contact Aili Industrial for project support.
