First, core points for equipment selection. Selection shall follow three principles: scenario adaptation, parameter matching and working condition compatibility.
- Determine the filtration grade according to purification requirements. F5-F6 grades are selected for general civil fresh air and ordinary factory ventilation; F7-F8 grades are adopted for industrial production, packaging & printing and precision processing workshops. High-grade cleanrooms can form a three-stage filtration system combining pre-filters and HEPA filters.
- Match equipment specifications according to system air volume. Calculate the required filtration area combined with the air volume of air handling units and duct wind speed. Avoid matching small-size filters with high air volume conditions, which will lead to sharp rise of air resistance and reduction of filtration efficiency. Under normal conditions, the air volume of a single pocket air filter shall be controlled within 60%-80% of the rated air volume to reserve sufficient operating margin.
- Select frame materials according to working conditions. Galvanized steel frames are used for dry and normal-temperature environments; stainless steel frames are suitable for humid environments; aluminum alloy frames are applied to scenarios requiring frequent disassembly and lightweight design; flame-retardant filter media must be adopted for industrial sites with flame retardant requirements.
Second, standardized installation process. Complete pre-installation preparation before construction: clean dust and debris inside the air handling unit, inspect the integrity of equipment appearance, and confirm that filter pockets are free of damage, frames are not deformed, and sealing gaskets are intact without falling off. The installation shall meet three requirements: flat placement, tight sealing and firm fixation. Embed the filter steadily into the installation slot of the air cabinet, ensure full contact between the frame and the contact surface of the air cabinet without gaps or offset. Filter pockets shall hang naturally without extrusion, folding or adhesion, to avoid blocking airflow and reducing effective filtration area. When multiple filters are installed side by side, keep uniform spacing and alignment, maintain horizontal and vertical placement, and prevent height misalignment. After installation, manually check the fixing condition to confirm no looseness or offset under slight shaking, and no air leakage gaps on the sealing surface.
Third, system commissioning and acceptance standards. No-load commissioning and load test shall be carried out after installation. During no-load commissioning, run the ventilation system at low speed for 30 minutes, observe the equipment operating status, and confirm no abnormal noise, no falling or shaking of filter pockets and no air leakage. In the load test phase, gradually increase the system air volume to the rated working condition, test the operating air resistance and filtration efficiency. The actual operating resistance shall not exceed the maximum rated resistance of the filter, and the filtration efficiency shall comply with the corresponding grade standards. Meanwhile, test the uniformity of outlet air with an anemometer, ensuring the air volume difference of each area ≤10%, without local air volume attenuation or blind zones of filtration. During acceptance, focus on checking common defects including sealing air leakage, filter pocket deformation and installation misalignment. The equipment can be officially put into use only when all indicators meet the standards.
In addition, for engineering operation and maintenance: record the initial air resistance and air volume parameters after installation and commissioning, which serve as reference data for later maintenance and replacement. When the operating resistance exceeds twice the initial resistance or the filtration efficiency decreases significantly, clean or replace the filter pockets in a timely manner to guarantee continuous and stable operation of the purification system. Standardized selection, installation and commissioning are the key to maximize the performance of pocket air filters and reduce operation and maintenance costs.
