FFKM O-Rings | Ultimate Chemical & High Temperature Seals

What is an FFKM O-ring?

FFKM (perfluoroelastomer) offers near-universal chemical resistance and top-tier heat capability—extreme chemical o-rings for acids, solvents, plasma, and vacuum.

Typical window: -15°C to +327°C (grade-dependent). Closest to PTFE chemically, while remaining elastic for sealing.

Composition & Properties

Perfluorinated backbone yields PTFE-like inertness with elastomeric sealing. Used in semiconductor, chemical processing, pharma, plasma/vacuum equipment.

• Hardness: 70–90 Shore A; common 75/80A with low compression set at high temperatures.
• Chemical: resists nearly all acids/bases/solvents/fuels/gases; very few exceptions.
• Heat: can sustain ~300°C class; short-term higher depending on grade.

Temperature Range

• Continuous: about -15°C to +327°C (grade-specific).
• High-temp: maintains low compression set at elevated temperatures; ideal for hot reactors and chambers.
• Low-temp: less flexible than silicone/NBR; ensure adequate compression at low temp.

Chemical Compatibility

• Good for: strong acids/bases, ethers/ketones/esters, aromatics/chlorinated solvents, fuels, oxidizers, plasma/vacuum.
• Rare exceptions: some fluorinated chemicals or molten metals—verify.
• Clean/particulate: semiconductor/vacuum grades available for low contamination.

Advantages

• Ultimate chemical resistance: suitable for nearly all media.
• High-temperature endurance: ~300°C class with low compression set.
• Clean options: semiconductor/vacuum grades with reduced particles.
• Lowest risk: best choice for critical equipment and costly downtime.

Applications

• Semiconductor/vacuum/plasma: reaction chambers, vacuum flanges, chemical lines.
• Chemical processing: strong acids/bases, aromatics/chlorinated solvents, high-temp reactors/pumps/valves.
• Pharma/fine chemical: combines cleanliness and corrosion resistance.
• Oil & gas/energy: extreme-service seals, alternative to metal seals for easier installs.

Size Coverage (AS568 / Metric)

• AS568 and metric/large/custom profiles available; batch labeling for traceability.
• Common 75/80A; custom colors/batches if needed.
• Compression/extrusion/finish guidance provided for hot/chemical service.

Ordering & Traceability

• Plan ahead for critical media; batch photos/barcodes for traceability.
• Share media/temp/pressure/cleanliness needs to match semiconductor/industrial grades.
• Mixed MOQ 1; custom large/odd sizes and colors available per project.

FAQs

• FFKM vs FKM: FFKM is far stronger in chemistry/heat; FKM is cheaper if compatible.
• Low temp? FFKM is modest at low temps—verify compression; consider PTFE/metal seals if needed.
• Ultra-clean? Choose semiconductor low-particle grades.
• Cost control? If compatible, downgrade to FKM/HNBR/PTFE; otherwise keep FFKM to minimize risk.

Installation & Selection Tips

• Compression: static 15–25%; choose moderate compression at high temp to limit set.
• Extrusion control: add backup rings for high pressure; groove Ra 0.8–1.6 μm.
• Storage: sealed, away from heat/light; avoid particulate contamination.