Polyester Pleated Coated Filter Bags

Based on conventional polyester membrane-coated needle-punched felt, pleated polyester membrane-coated filter bags incorporate a pleated structure design that significantly increases the filtration area within the same installation space (typically 50%–150% that of traditional round bags), thereby achieving lower filtration pressure drop, reduced operating resistance, and more significant energy savings. The PTFE microporous membrane laminated to the surface of this product ensures highly efficient surface filtration and easy dust removal, while its pleated structure further optimizes system performance, allowing it to directly replace existing filter bags without requiring structural modifications to the dust collector itself.

In terms of applicable operating conditions, the continuous operating temperature typically does not exceed 130°C, with a peak of up to 150°C; it offers moderate resistance to acids, alkalis, and abrasion. It is widely applicable in industries such as steel, cement, foundries, grain processing, and wood processing—where large-volume, ambient-temperature dust needs to be treated, or where there are high requirements for dust collector space utilization and operational energy efficiency.

Key Features of the Pleated Structure (The Main Difference from Standard Cylindrical Coated Filter Bags)

Under conditions of identical perforation diameter in the perforated plate and identical bag length: Effective filtration area increases by 2.0 to 3.5 times. Example: For a standard cylindrical bag measuring φ130 × 2000 mm, the filtration area is approximately 0.82 m²; a pleated filter bag of the same size can achieve an area of 1.8 to 2.8 m².

Core Performance Advantages

Two Major Benefits of Significantly Increased Filtration Area

① Reduced filtration air velocity: For retrofitting existing dust collectors, there is no need to add new housings or modify the perforated plate—simply replace the filter bags. Lower filtration air velocity → lower operating pressure drop and reduced cleaning load. ② New dust collectors: For the same air handling capacity, the housing volume can be reduced, saving on equipment investment.

Inherent Advantages of PTFE-Coated Filter Bags (Similar to Flat-Panel Coated Felt)

1) High filtration efficiency for ultrafine dust: Efficiency for particles ≥0.3 μm is >99.99%, consistently achieving ultra-low emissions (≤5 mg/Nm³);

2) Surface filtration ensures dust adheres only to the outer surface of the membrane, enabling thorough pulse-jet cleaning and preventing internal dust accumulation;

3) The smooth film surface prevents dust adhesion; when combined with triple-protection treatment, it can handle conditions with slight condensation and hygroscopic dust;

4) Custom pleated, anti-static, film-coated filter bags are available for explosive-proof applications involving pulverized coal, lithium battery powder, and combustible dust.

Advantages in Operating Energy Consumption and Service Life

Reduced filtration air velocity → Less erosion on the filter bags; cleaning frequency can be reduced, lowering compressed air consumption; The filter bag wear rate is lower than in high-velocity conditions, resulting in a longer theoretical service life.

1. Weaknesses and Usage Limitations (Key Considerations for Selection)
2. Dust tends to accumulate in the crevices of the pleats, creating dead zones. In conditions with highly adhesive dust, high humidity, or heavy oil mist, dust easily accumulates at the pleat valleys, leading to long-term bridging and bag clogging; not suitable for flue gas containing highly adhesive tar or asphalt.
3. Higher requirements for dust cleaning: The pleated structure results in a longer dust-detachment path; if the pulse pressure is too low or the blowpipe design is improper, cleaning at the pleat valleys is incomplete, leading to a gradual rise in differential pressure.
4. Lower abrasion resistance than standard cylindrical filter bags: Stress concentration occurs at the pleat corners; when flue gas contains hard, angular particles (such as ore or grinding wheel dust), prolonged airflow erosion causes the film on the pleated edges to wear and crack more easily. Use with caution in highly abrasive conditions, or select thickened filter media.
5. Higher Cost: The membrane-coated filter media itself is expensive, and when combined with the pleating process, the unit price is significantly higher than that of standard straight-cylinder membrane-coated filter bags.
6. Temperature Limitations: The polyester substrate has a maximum continuous operating temperature of 130°C; if flue gas temperatures consistently exceed this limit, PPS pleated membrane-coated filter media must be used instead.

Suitable Operating Conditions

• Upgrading existing baghouse dust collectors to meet stricter standards, where space constraints prevent enlarging the housing;
• Ultra-fine dust and ultra-low emission environmental requirements (building materials, chemicals, drying dust, grain processing);
• Moderate humidity, no significant liquid oil mist; can be manufactured in an anti-static version for dust collection of flammable and explosive powders;
• When the number of holes in the dust collector’s perforated plate is limited and the total filtration area needs to be increased.