Medium-efficiency bag filter Medium-efficiency bag filters serve as the core intermediate hub in the three-stage air purification system. Specifically designed to capture suspended dust particles of 1-5μm, they undertake two crucial missions: first, providing pre-protection for end-stage high-efficiency filters (HEPA/ULPA) to significantly reduce their dust load and extend service life; second, directly purifying air with high dust concentration, and can be used as terminal filtration equipment in scenarios with moderate cleanliness requirements. Their bag-type structure is widely recognized as the optimal design in the medium-efficiency filtration field. With the characteristics of high dust-holding capacity and low resistance, they are extensively compatible with commercial and industrial purification systems.
I.Core Structure and Technological Innovation
1. Filter Media System: Gradient Interception, High Efficiency and Safety
Adopting a superfine synthetic fiber gradient composite structure to replace traditional glass fiber materials, it avoids the risk of fiber shedding during use.
A typical filter media hierarchy includes:
Outer layer: Melt-blown polypropylene fibers (15-25μm in diameter), responsible for pre-filtration and structural support;
Middle layer: Electrostatically charged PET fibers (5-8μm in diameter), enhancing the capture of sub-micron dust through electrostatic adsorption;
Inner layer: Glass fibers or PTFE-coated membranes (0.8-1.2μm in diameter), enabling deep interception of 1-5μm particles;
Functional layer: Some models are equipped with an antibacterial coating to inhibit microbial growth.
The filter media is available in multiple grades from F5 to F9, supporting cleaning or backwashing for reuse, and is suitable for different pollution scenarios.
2. Structural Design: Fluid Optimization, Stability and Durability
Bag Optimization: Adopting a V-shaped pleated design with an optimized pleat angle of 45°, which increases the effective filtration area by 28% compared with traditional straight bag types; the ratio of bag depth to bag spacing is set to 1:1.2, reducing air pressure drop by 15%;
Sealing Technology: Utilizing ultrasonic welding technology, the sealing strength reaches 35N/cm, with a leakage rate of <0.005%, and it can withstand temperature cycles from -40℃ to 120℃;
Support System: Built-in reinforced "bag support grid" to prevent bag shrinkage and deformation under high air flow and high dust load conditions, ensuring uniform air penetration through each filter bag.
3. Frame Configuration: Multi-Compatibility, Long-Lasting Durability
Multiple options are available for frame materials: aluminum profile frames, aluminum plate folded frames, galvanized frames and stainless steel frames. The protective net is made of galvanized or plastic-sprayed iron wire, suitable for different corrosive environments. The frame can be reused, and only the filter bag needs to be replaced during replacement, reducing long-term maintenance costs.
II. Core Advantages
Efficient Purification, System Protection: The filtration efficiency for core particle sizes of 1-5μm reaches 60%-95%, significantly reducing pollution to downstream equipment and extending the service life of high-efficiency filters by more than 30%;
Low Resistance and Energy Saving, Economical Operation: The optimized fluid structure reduces the energy consumption of system fans by 15%-25%. The washable filter media design reduces replacement frequency and lowers annual maintenance costs by 40%;
Strong Adaptability, Diverse Scenarios: Supports customized air volume, compatible with various systems from commercial air conditioners to industrial purification, and can withstand complex environments such as humidity and high dust;
Easy Installation, Simple Maintenance: The modular design of the frame and filter bag allows replacement without professional tools, and can be completed by a single person.
III.Applicable Scenarios
Commercial Building Field: Intermediate filtration for central air conditioning and ventilation systems, suitable for office buildings, shopping malls, hotels and other places to improve indoor air quality;
Industrial Purification Field: Air purification in pharmaceutical workshops, electronic factories, food processing plants to control dust concentration in the production environment;
Equipment Protection Field: Used as pre-filtration for precision air conditioners in data centers and air supply systems in automotive painting workshops to protect core equipment;
Terminal Filtration Field: Can be directly used as terminal filtration equipment in places with moderate cleanliness requirements, such as laboratories and hospital waiting areas.
