Industry Overview
The automotive industry is a major application area for fluoroelastomers and engineering plastics. A typical passenger vehicle uses approximately 20-30 fluoroelastomer seals, while new energy vehicles require 2-3 times more fluorinated materials than conventional vehicles. As emission standards become increasingly stringent (China VI / Euro VI), fuel system sealing materials must resist alcohol-containing fuels and acidic condensates. New energy vehicle battery pack seals require materials that combine electrolyte resistance with high-temperature performance. Meanwhile, automotive lightweighting and electrification trends are driving the widespread adoption of engineering plastics in structural and functional components.
FUERTAI provides a full range of material solutions for the automotive industry, covering powertrain, chassis, and electrical systems across conventional, hybrid, and battery electric vehicle platforms, helping manufacturers meet increasingly demanding performance and environmental requirements.
Core Material Solutions
Fuel System Sealing: Ternary FKM offers excellent fuel resistance and is widely used in fuel pump seals, fuel injector O-rings, and fuel line connector seals. With the promotion of ethanol and methanol gasoline, ternary FKM's superior resistance to alcohol-containing fuels becomes even more critical, with volume change controllable within 5%, far better than binary FKM's 15%+.
Engine Peripheral Sealing: HNBR (hydrogenated nitrile rubber) is the preferred material for engine peripheral seals, used in timing belts, transmission shaft oil seals, and crankshaft front seals. HNBR offers excellent hot oil aging resistance (continuous service at 150°C) along with high strength and good wear resistance, meeting the demanding requirements of engine compartment environments.
Electrical System Insulation: FEP and ETFE wire and cable insulation provides excellent heat resistance (FEP 200°C / ETFE 150°C) and electrical insulation properties, along with resistance to fuel, oil, and ozone, making them ideal insulation materials for automotive wiring harnesses. ETFE also offers good cut-through resistance and radiation resistance for demanding engine compartment routing.
Engineering Plastic Components: POM (polyacetal) is used for fuel system components, gears, and clips, offering excellent wear resistance and dimensional stability. PA66/PA6 nylon is used for connectors, switches, and sensor housings; glass-fiber reinforced grades can replace metal structural components for weight reduction. ABS is used for interior panels and dashboard frames, combining good surface quality with mechanical performance.
Technical Highlights
| Application | Recommended Material | Key Performance | Service Temperature |
|---|---|---|---|
| Fuel Pump Seal | Ternary FKM | Alcohol fuel resistance | -40 to 150°C |
| Transmission Seal | HNBR | Hot oil aging resistance | -40 to 150°C |
| Wire Harness Insulation | FEP/ETFE | Heat & insulation resistance | -40 to 200°C |
| Gears/Clips | POM | Wear & dimensional stability | -40 to 120°C |
| Battery Pack Seal | Ternary FKM | Electrolyte resistance | -40 to 150°C |
Key technical considerations for automotive material selection:
- Alcohol Fuel Resistance: Under China VI standards with increased fuel alcohol content, ternary FKM must replace binary FKM to prevent excessive seal swell and failure
- Compression Set: Engine compartment seals are under long-term high-temperature compression; low compression set formulations are essential
- Coolant Resistance: Seals in contact with coolant must pass ASTM D471 coolant immersion testing with volume change ≤10%
- Flame Retardancy: Electrical system materials must meet UL94 V-0 rating; FEP and ETFE naturally meet this requirement
Application Cases
Fuel Injector Seal: A China VI engine fuel injector O-ring exposed to gasoline with 10% ethanol, temperature -40°C to 125°C, using ternary FKM peroxide cure compound, hardness 70±5 Shore A, fuel volume change ≤3%, passing 500,000 km durability testing.
Transmission Oil Seal: An 8-speed automatic transmission output shaft seal in ATF fluid, temperature -40°C to 150°C, using HNBR material, hardness 80±5 Shore A, lip wear life exceeding 300,000 km.
Battery Pack Seal: A BEV battery pack sealing strip exposed to electrolyte vapor, temperature -40°C to 120°C, using ternary FKM extruded profile, compression set (150°C×22h) ≤20%, meeting IP67 protection rating.
Selection Recommendations
FUERTAI recommends following the ’Regulations First, Conditions Driven’ principle for automotive material selection: First confirm applicable regulatory standards (emissions, flame retardancy, food contact, etc.), then select material type and grade based on specific conditions (temperature, media, pressure, motion type). For new energy vehicles, electrolyte-resistant ternary FKM is recommended for battery pack sealing; conventional vehicle fuel systems must use ternary FKM. FUERTAI offers one-stop services including material recommendation, sample prototyping, and volume supply.
