Applications and Industry Trends of Non-Asbestos Sheets

— Hongwo Factory · Materials Engineer Zhao Lei

1. Bottom line first: the asbestos era is over.

The EU implemented a full ban on asbestos in 2005. In China, the May 2025 update to the Occupational Disease Prevention Law labels asbestos dust as “Category I — Strict Control.” Authorities can impose daily penalties without any greatest limit. Non-asbestos rubber sheets aren’t optional anymore. They are now required for factory shipments.

(Keywords used throughout: Applications of Non-Asbestos Sheets, Industry Trends of Non-Asbestos Sheets. Alternate names inserted in text: non-asbestos rubber sheet, asbestos-free gasket sheet, non-asbestos sealing sheet, asbestos-free rubber gasket, aramid-reinforced non-asbestos sheet.)

2. Measured advantages from Hongwo’s production lines

• Temperature window: long-term −40 °C to 150 °C; instantaneous 200 °C for 1 h. Compression set 12% ± 2%; rebound ≥ 45%.

• Mechanical & chemical resistance: transverse tensile ≥ 12 MPa. ASTM F146 fuel-oil immersion, 5 h: weight gain < 8%; thickness swell < 5%.

• Environmental credentials:

  • Passes REACH, RoHS, and ELV (End-of-Life Vehicles) directives.

  • EU export parts come with SCIP numbers.

• Manufacturing friendliness and safety:

  • Single-cut die cutting leaves no residue at 0.5 mm thickness.

  • Rotary cutting can handle 10,000 sheets without needing a blade change.

  The team reduced workshop dust to 0.8 mg/m³, well below the occupational limit of 2 mg/m³.

3. Top 10 In-Service Applications in 2025 (All from Hongwo this year — traceable by batch number)

1. Euro 6 diesel engine oil pan

   • Spec: 1.2 mm aramid fiber + NBR (nitrile rubber). Oil-resistant to 120 °C. Bolt torque 22 N·m. 400-hour bench thermal shock test: no leakage.

2. Offshore wind turbine pitch gearbox end cover

   • Spec: full-diameter sheet Φ850 mm. Tested marine bio-oils with 96 hours of salt spray showed no blisters. The compression set retention was 94% after the salt spray.

3. Lithium battery foil rolling vacuum duct

   • Spec: 2.0 mm backing plate with PTFE surface coating. HF acid mist resistant. After six months of service, the inspection showed no cracks.

4. High-speed rail brake valve body

   • Spec: ultra-thin 0.8 mm gaskets. Need: 10 bar airtightness with 1 s pressure drop < 0.01 bar. First-pass yield 99.7%; unit price replaces imported parts with a 34% cost reduction.

5. Urban gas PE ball valve flange

   • Spec: 3.0 mm thickened sheet, Shore A hardness 90, compensates for flange surface irregularity up to 0.2 mm. Passes 1.5 PN hydrostatic test for 1 h with zero seepage.

6. Marine auxiliary seawater pump

   • Spec: neoprene (CR)-based sheet; seawater 5% NaCl at 90 °C: 72 h tensile retention 88%. DN250 flange sets: 2,000 units have already shipped.

7. Food-grade filling machine

   • Spec: white EPDM non-asbestos sheet compliant with FDA 21 CFR 177.2600. Hot-water CIP 85 °C / 30 min cycles × 1,000 — no discoloration, no odor migration.

8. PV laminator hot-press exhaust/heating line

   • **Spec:** 1.5 mm silicone-faced composite sheet. It resists saturated steam at 180 °C. It can handle continuous press cycles for 20 hours and has a rebound of ≥ 40%. This solution eliminates the customer’s monthly gasket replacement issue.

9. Transformer oil tank cover gasket

   • Spec: 1.0 mm sheet with 0.1 mm stainless-steel mesh core. Axial burst resistance 25 bar. Oil immersion at 150 °C for 168 hours shows lateral expansion of less than 3%. This method replaces traditional asbestos-copper wire gaskets.

10. Hydrogen fuel cell bipolar plate water chamber

    • Spec: 0.5 mm ultra-low-chloride formulation, Cl⁻ < 50 ppm. Proton-exchange membrane contamination test: 1,000 h degradation < 1%. Shipped with stacks to North America.

4. Where the industry is heading (based on Hongwo’s H1 bidding data)

• Bio-based latex replaces about 30% of petroleum-based nitrile. It uses itaconic acid and cardanol, which come from cashew nuts. The anticipated carbon footprint reduction is ~18%. EU customers have already signed pilot trials.

• Nano-fiber reinforcement: Adding 2% modified SiO₂ nanotubes boosts transverse strength by about 26%. It also allows us to reduce wall thickness by around 20%. This makes it ideal for ultra-thin heat-spread plate flanges in electronics.

• Self-alerting gaskets include a conductive mesh that lowers resistance at the first leak. This sets off an alarm. It cuts emergency response times in petrochemical plants from hours to minutes.

• Closed-loop recyclability: pyrolysis recovery yields >70% rubber phase and reusable fillers. The EU expects to mandate ≥40% recyclable content for sealing components by 2026.

• Digital delivery: Each batch has a QR code. You can easily download the compression-rebound curve, RoHS reports, and raw material batch numbers. Audits no longer need paper trails.

5. Summary

Non-asbestos rubber sheets have transitioned from a replacement option to an operational necessity.

Success in four key areas helps suppliers excel in Euro-6 engines, offshore wind, hydrogen, and marine markets:

• Temperature resistance

• Media resistance

• Environmental compliance

• Cost

Hongwo’s 2025 capacity: 23,000 m²/day, thickness range 0.3–5.0 mm, 48-hour dispatch for standard orders. Send us flange dimensions, bolt torque, and temperature profiles. In ten minutes, we will suggest a sheet formulation and predict its lifespan. This way, your sealing parts will last longer and will not be consumables.

— Zhao Lei, Materials Engineer, Hongwo Factory