Kaxite Sealing manufactures PTFE filter bags by laminating a 100% expanded PTFE (ePTFE) microporous membrane onto a chosen support fabric — PTFE felt, PPS, P84® polyimide or fiberglass. The membrane traps particulate on the surface instead of letting it embed in the fabric, delivering higher airflow, lower pressure drop and longer bag life in high-temperature flue gas. Procurement teams choose us for factory-direct pricing, full dimension traceability and 15–25 day lead times on bulk orders.
Membrane expansion, lamination, cutting and stitching all run inside our Ningbo plant. No trading layer, so your PTFE filter bag price stays stable even on repeat orders. Annual volume discounts available.
Standard lengths 1.5–8.0 m and diameters 120/130/150/160 mm — plus any non-standard size to drawing. Send an old bag sample or dimensions, and we return finished custom PTFE filter bags ready to install.
Choosing the right base fabric is critical. We help match PTFE felt, PPS, P84® polyimide, fiberglass or anti-static felt to your gas stream temperature, chemistry and dust load. Documented test data supplied.
ePTFE membrane laminated to felt achieves > 99.99 % capture on 0.3 μm particulate — including PM2.5 — delivering clean stack emissions and stable pressure drop for 4–6 years in well-controlled boilers.
Conductive-fibre grades for combustible dust service, oleophobic grades for oil-laden streams, and hydrolysis-resistant grades for high-moisture flue gas. Samples available for evaluation.
Batch records, membrane test reports and full resin-lot traceability. Third-party testing (SGS, TÜV) on request, with FDA and RoHS declarations where required.
Fabricated from a 100% expanded PTFE microporous membrane laminated onto a superior quality support fabric — Polypropylene, non-woven PET or PE, PTFE felt, PPS or fiberglass. The membrane traps particulate on the surface, ensuring surface filtration instead of depth filtration — the baghouse runs at higher airflow with lower pressure drop. Breathable with homogeneous pore size distribution, non-aging under normal operating conditions, chemically inert across pH 0–14, and does not contaminate the media it filters. Suitable for high-humidity environments.
| Component | Material Options | Key Characteristics |
|---|---|---|
| Membrane | 100% Expanded PTFE (ePTFE) | High porosity, controlled pore size, hydrophobic, laminated for durability |
| Substrate | PTFE felt, PPS felt, P84® polyimide, fiberglass | Structural support — matched to temperature and chemistry |
| Hardware | SS 304 / 316, powder-coated steel, PP / POM plastic | Secure tube-sheet fit, corrosion-resistant options |
| Seam | Hot-melt PTFE seam or sewn PTFE thread | Seam strength ≥ fabric, no leak paths |
| Parameter | Specification | Notes |
|---|---|---|
| Filtration Efficiency | > 99.99 % on 0.3 μm | Can be tailored to specific efficiency |
| Service Temperature | -240 to +260 °C | Short peaks up to +280 °C possible |
| Air Permeability | 2 – 15 CFM/ft² | Dependent on membrane and substrate |
| Basis Weight | 12 – 18 oz/yd² | Includes substrate and membrane |
| Chemical Inertness | pH 0 – 14 | Acid, alkali, solvent resistant |
| Surface Finish | Hydrophobic / oleophobic | Non-stick, easy cake release |
MOQ negotiable for trial and pilot baghouse installations. Free short sample lengths of the standard membrane and substrate combinations are available for membrane integrity and permeance evaluation.
15–25 days for standard bag dimensions after confirmation of substrate and drawing. Longer for non-standard cuffs, anti-static grades or large bulk orders. FOB Ningbo / Shanghai, CIF and DDP terms available.
Membrane-integrity test data with every shipment. Third-party testing (SGS, TÜV) on request. Full traceability from ePTFE resin lot to finished bag, with pre-shipment photo and video verification on bulk orders.
Service life depends on temperature, chemistry, dust abrasiveness and cleaning frequency. In well-controlled high-temperature applications like coal-fired boilers, quality ePTFE bags typically run 4–6 years or more. In severe service such as waste incineration, 2–3 years is common — still well beyond alternative filter media.
Yes — this is one of their key advantages. The ePTFE membrane is inherently hydrophobic (water-repelling) and oleophobic (oil-repelling), so moist or sticky particles cannot blind the fabric. The dust cake forms on the surface and releases cleanly during each pulse, maintaining a stable low pressure drop.
A PTFE membrane bag has a thin microporous ePTFE film laminated to the substrate — true surface filtration with tight, controlled pore size. A PTFE coated bag has PTFE resin applied to the fibres, adding some chemical resistance and cake-release improvement, but without the fine controlled pore structure. Membrane bags offer far better sub-micron efficiency.
Yes — they are the preferred choice for modern pulse-jet cleaning. Surface filtration lets the dust cake release cleanly with each pulse, and the membrane and substrate withstand the repeated mechanical stress of pulse cleaning over many years. Correct bag tension and cage design are important for peak performance.
The substrate follows your gas-stream temperature and chemistry. Up to 260 °C with acid presence: PTFE felt. Around 190 °C with good acid resistance: PPS (Ryton). Similar range with a different fibre structure: P84 polyimide. High-temperature alkaline conditions: fiberglass. Our engineers will recommend the optimal construction based on your process data.
Sustained high pressure drop that cleaning cannot reduce, visible dust emissions from the stack, physical tears or seam failures seen during inspection, or simply reaching the projected end of service life based on plant data. Regular inspection is key to proactive maintenance.
Yes — customization is a core strength. We manufacture to virtually any dimension: length, diameter, cuff style (snap-band, rope, flanged) and specific hardware requirements. Providing an old bag sample or detailed drawing ensures a perfect fit for your existing tube sheet.
Store in a cool, dry place away from direct sunlight. Keep in original packaging until installation and handle with clean gloves to avoid transferring skin oils to the membrane. Inspect each bag for shipping damage before use. Under these conditions, PTFE has effectively unlimited shelf life.
Send us your bag dimensions (length, diameter, cuff style), gas-stream temperature and chemistry, dust characteristics, quantity per year, or an old bag sample for reverse-engineering. Our export team replies within 24 hours and confirms substrate selection, lead time, packaging and documentation before you place a bulk order.
