If you’re speccing an air, oil-mist, or liquid coalescing line right now, you’ve probably bumped into composite fiberglass filter paper. To be honest, it has moved from niche to default in many projects—mostly because engineers are chasing higher capture at lower ΔP without paying a penalty in service life.
Three things I keep hearing: tighter micron control (um1–um30), migration to multi-layer microglass + PET scrims, and cert-ready documentation for ISO 16890/ASHRAE 52.2. Surprisingly, even oil-gas separators are borrowing HEPA-style test language to compare apples to apples.
Composite fiberglass filter paper blends micro-glass fiber layers with PET nonwoven reinforcement and a resin system—usually acrylic or epoxy—calendered for pore-size control. The result: high efficiency on submicron aerosols, decent dust holding, and mechanical stability in cartridges and pleats.
| Grade | Nominal Cut | Basis Weight | Initial ΔP | Efficiency | Max Temp |
|---|---|---|---|---|---|
| UM1 | ≈1 µm | 85–110 g/m² | 80–110 Pa @ 5.3 cm/s | ≥99.95% @ 0.3 µm | 120–150°C |
| UM5 | ≈5 µm | 120–160 g/m² | 60–90 Pa | 95–99% @ MPPS | 120–150°C |
| UM30 | ≈30 µm | 160–220 g/m² | 40–70 Pa | 70–90% (coarse) | 120–150°C |
Real-world use may vary by pleat height, resin %, and face velocity. Many customers say UM5 hits a sweet spot for oil-mist coalescers.
Composite fiberglass filter paper production (Handan, Hebei, China, Second Building and Studying No21 Shiji Street):
Use it in oil-gas separation, liquid polishing, cleanroom pre-HEPA stages, compressor intake filters, lab fume capture. Advantages: high capture of submicron aerosols, stable pleatability, lower initial ΔP, and predictable loading curve. Actually, it also holds up nicely at elevated temps up to ~150°C.
| Vendor | Media Type | Certs | Lead Time | Notes |
|---|---|---|---|---|
| FiltersMaterial (Hebei) | Micro-glass/PET composite | ISO 9001; RoHS/REACH | 2–4 weeks | Custom um1–um30, roll or cut. |
| Global OEM A | Glass + synthetic blends | ISO 16890 reports | 4–6 weeks | Strong HEPA/ULPA lineup. |
| EU Supplier B | Coalescing media | CE, ISO 12500 data | 3–5 weeks | Premium pricing, low MOQ. |
You can dial fiber diameter, binder %, and PET scrim weight to balance stiffness vs. permeability. For one customer, a UM5 variant with 6% acrylic binder cut initial ΔP by ~12% while maintaining 99.5% @ 0.3 µm (ISO 29463 MPPS); dust-holding improved ~9% on an ASHRAE 52.2 loading curve. It seems that minor calendering tweaks matter more than most expect.
- Electronics plant (SEA): swapped in composite fiberglass filter paper pre-HEPA; ΔP dropped ~18 Pa, HEPA life extended ~5 months.
- CNC shop (EU): oil-mist coalescing stage using composite fiberglass filter paper UM5; 30% fewer changeouts over 10 months.
- Food packaging (NA): liquid polishing with composite fiberglass filter paper UM10; clearer effluent, ISO 4406 improved from 18/16/13 to 16/14/11.
If you’re unsure, spec UM5 or UM10, face velocity 5.3–8.5 cm/s, and request ISO 16890 or ISO 12500 test sheets. And, yes, ask for calendering parameters—small changes, big results.
