PTFE (Polytetrafluoroethylene) Needle Punched Felt Filter Bag
PTFE needle punched felt filter bags from LYH fit waste incineration, hazardous waste treatment, chemical processing, glass furnaces, and the most chemically aggressive flue gas applications. Buyers choose PTFE filter bags when they need ultimate chemical resistance, sustained service up to 260 °C, total hydrolysis immunity, and zero compromise in highly oxidizing or acid-laden environments where PPS and other media fail.
We supply PTFE / Polytetrafluoroethylene filter bags from China with custom size discussion, fabric weight options (550–850 GSM), and full surface treatment support including PTFE membrane lamination for ultra-low emission compliance. If your project requires a specific bag diameter, length, top/bottom construction, or ePTFE membrane match for ≤ 5 mg/Nm³ emission targets, we can review the RFQ and pair the right PTFE felt to your dust collector.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Material | 100% PTFE (Polytetrafluoroethylene) staple fiber, PTFE / glass fiber scrim-supported needle felt |
| Continuous Operating Temperature (Dry) | 240–260 °C / 464–500 °F |
| Continuous Operating Temperature (Moist) | 240–260 °C / 464–500 °F |
| Maximum Short-Term Surge Temperature | 280 °C / 536 °F |
| Specific Density | 2.3 g/cm³ |
| Moisture Regain (20 °C, 65% RH) | 0% |
| Standard Fabric Weight | 550 / 650 / 750 / 850 GSM (customizable) |
| Air Permeability | 8–14 m³/m²/min @ 200 Pa |
| Tensile Strength (Warp / Weft) | ≥ 800 N / 5×20 cm |
| Filtration Efficiency | ≥ 99.99% (with ePTFE membrane: ≥ 99.999%) |
| Combustibility | Non-flammable (LOI ≥ 95) |
| Chemical Resistance | Resistant to virtually all acids, alkalis, and organic solvents |
Material Properties
Unmatched Chemical Resistance — PTFE is chemically inert across the entire pH range and resistant to virtually every industrial acid, alkali, organic solvent, and oxidizing agent. It withstands continuous exposure to concentrated sulfuric acid, hydrochloric acid, hydrofluoric acid, caustic soda, and aqua regia at elevated temperatures — conditions that destroy every other commercial filter media.
Total Resistance to Oxidizing Agents — Unlike PPS, P84, and aramid (which degrade under high O₂, NOx, or halogen exposure), PTFE is fully stable in the most oxidizing flue gas environments. This makes it the only viable choice for hazardous waste incinerators, fluorine-containing processes, and certain chemical applications.
Highest Continuous Operating Temperature Among Synthetic Fibers — Sustained service up to 260 °C dry / moist with short-term peaks to 280 °C, combined with non-flammable behavior (LOI ≥ 95) — the highest of any commercial filter fiber.
Zero Moisture Regain & Total Hydrolysis Immunity — PTFE absorbs zero moisture and is completely unaffected by saturated steam, acid dew point, or condensation. Performance remains constant across the operational humidity spectrum.
Excellent Cake Release & Low Pressure Drop — PTFE’s intrinsically low surface energy gives it the lowest coefficient of friction of any solid material. Dust cake releases cleanly during pulse cleaning, resulting in lower differential pressure, less compressed air consumption, and longer filter bag life.
Long Service Life Under Extreme Conditions — In typical hazardous waste and chemical applications, PTFE filter bags routinely deliver 5–8 years of service life, often 2–3× longer than PPS or P84 in equivalent harsh conditions.
Limitations to Note — PTFE has lower mechanical strength than PPS, P84, or aramid, and may elongate under continuous load at elevated temperatures. Proper cage support and limited bag length are essential. PTFE is also more expensive than alternative high-temperature media — but its long service life typically yields lower lifecycle cost in challenging applications.
Available Surface Treatments
| Treatment | Function | Recommended For |
|---|---|---|
| Singeing | Removes loose surface fibers via flame; improves cake release | Standard high-chemistry dust |
| Calendering / Glazing | Heated rollers densify the surface; enhances surface filtration | Fine-particle capture, low pressure drop |
| Heat Setting | Stabilizes felt dimensions, eliminates shrinkage during operation | All applications |
| ePTFE Membrane Lamination | Microporous expanded-PTFE membrane on dust side; emissions ≤ 5 mg/Nm³, near-zero penetration | Ultra-low emission compliance, fine PM2.5 capture |
| Anti-Static | Conductive carbon fiber or stainless-steel filament; surface resistance 10³–10⁸ Ω·cm | Combustible dust in hazardous waste, chemical processing |
| Water & Oil Repellent (WO) | Enhanced moisture and oil rejection finish | Sticky, oily, condensate-prone streams |
Bag Construction
- Top Constructions — Snap band, flange top, ring top, soft cuff, raw edge, strap top
- Bottom Constructions — Disc bottom, flat bottom, reinforced double-bottom, wear-strip bottom
- Sewing — 3-needle chain stitch with PTFE thread (mandatory for chemical compatibility); overlock or lockstitch on bottoms
- Reinforcement — Optional wear strips, custom skirts, double-bottom reinforcement; cage design must accommodate PTFE’s tendency to elongate under load
Standard Sizes & Customization
| Dimension | Range |
|---|---|
| Diameter | Φ100 / 120 / 125 / 130 / 150 / 160 / 180 / 250 mm (or custom) |
| Length | 1,000 – 8,000 mm (custom lengths available) |
| Tolerance | Diameter ± 2 mm, Length ± 5 mm |
Non-standard sizes, special top/bottom configurations, and OEM patterns produced from your drawings or sample bag.
Industry Applications
- Municipal & Hazardous Waste Incineration — MSW, medical waste, industrial hazardous waste — the largest global application of PTFE filter bags
- Cement Kilns — alternative fuel co-processing with elevated chlorine, fluorine, and SO₃ content
- Chemical Processing — fluorochemicals, halogenated organics, strongly acidic/alkaline streams
- Glass & Fiberglass Manufacturing — furnace exhaust at high temperature with corrosive components
- Carbon Black Production — process tail gas dedusting
- Power Generation — coal-fired boilers requiring ultra-low emission compliance (≤ 5 mg/Nm³)
- Steel & Non-Ferrous Smelting — high-temperature exhaust with halogen content
- Pharmaceutical & Specialty Chemicals — solvent-laden, corrosive, or contamination-sensitive streams
- Asphalt Mixing — premium-grade installations requiring extended service life
- Ultra-Low Emission Compliance — any application with mandated ≤ 10 mg/Nm³ or ≤ 5 mg/Nm³ targets
Why Choose LYH PTFE Filter Bags
- Premium PTFE fiber — sourced from leading global producers; PTFE/fiberglass scrim-supported felt for stability under load
- Strict QC on fabric weight, air permeability, tensile strength, chemical resistance, ePTFE membrane integrity
- Full customization — any size, any top/bottom, any treatment combination
- Engineered for extreme duty — proven configurations for hazardous waste, chemical, and ultra-low emission applications
- PTFE-on-PTFE sewing — all seams use PTFE thread for full chemical compatibility
- Fast lead time — standard sizes ship in 15–25 days (PTFE production cycle longer than standard media)
- Engineering support — application engineers help match media to your gas chemistry, halogen content, and emission target
- Reliable logistics — individually wrapped, ring-up packing, sea / air / courier shipment worldwide
FAQ
Q1: What is the maximum operating temperature of PTFE filter bags? PTFE filter bags operate continuously at up to 260 °C (500 °F) in both dry and moist conditions, with short-term peaks up to 280 °C. PTFE has the highest sustained operating temperature among synthetic fibers and is non-flammable (LOI ≥ 95).
Q2: Why choose PTFE over PPS or P84? PTFE is chosen when chemical resistance is the primary requirement — particularly in flue gas with high O₂, NOx, halogens, or extreme acid/alkali content. While PPS and P84 are more cost-effective in normal conditions, both fail under aggressive oxidation. PTFE is the only fiber stable across the entire chemical spectrum, including hydrofluoric acid, fluorine, and aqua regia.
Q3: When is PTFE membrane (ePTFE) lamination required? ePTFE membrane is essential for: (1) ultra-low emission compliance ≤ 5 mg/Nm³, (2) fine PM2.5 capture, (3) sticky or condensable particulates, (4) any application where dust must be captured on the surface rather than embedded in the felt. The membrane provides surface filtration with virtually zero particle penetration.
Q4: Why is PTFE more expensive than other filter media? PTFE fiber production is inherently more complex and uses higher-cost raw materials. However, PTFE filter bags typically deliver 5–8 years of service life in harsh conditions — 2–3× longer than PPS or P84 — yielding lower total lifecycle cost in chemical, hazardous waste, and ultra-low emission applications despite the higher upfront price.
Q5: Does PTFE elongate under operation? Yes. PTFE has lower tensile strength than PPS or P84 and may elongate (creep) under continuous mechanical load at elevated temperature. Proper cage design, limited bag length, and adequate scrim support are essential. LYH PTFE filter bags use PTFE/fiberglass composite scrim to maintain dimensional stability throughout service life.
Q6: Can PTFE filter bags be made anti-static? Yes. Anti-static PTFE with conductive carbon fiber or stainless-steel filament is available for hazardous waste incineration, biomass, and other combustible-dust applications. Surface resistance is controlled to 10³–10⁸ Ω·cm.
Q7: Are PTFE filter bags suitable for ultra-low emission compliance? Yes — PTFE filter bags with ePTFE membrane lamination are the gold-standard solution for ultra-low emission targets (≤ 10 mg/Nm³, often ≤ 5 mg/Nm³). The combination of PTFE substrate + ePTFE membrane delivers ≥ 99.999% filtration efficiency with industry-leading service life.
Q8: What information do I need to provide for a quote? (1) bag dimensions, (2) top/bottom construction, (3) operating temperature & humidity, (4) flue gas composition (O₂, halogens, SOx, NOx, HF, HCl), (5) dust type & concentration, (6) emission requirement, (7) quantity. A drawing or sample bag is even better.
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