FFKM vs FKM – THE DIFFERENCE THAT DEFINES PERFORMANCE IN HIGH-EFFICIENCY SEALING SOLUTIONS

A single letter makes all the difference — and marks a major technological leap.
In the field of industrial sealing solutions, FFKM and FKM are two widely used types of fluorocarbon elastomers — each with its own characteristics, advantages, and limitations.

In this article, Filterfine Vietnam, the official distributor of DuPont™ Kalrez® FFKM, will help you understand:

• What are the key differences between FFKM and FKM?

• Which applications suit each material?

• And why Kalrez® FFKM is regarded as the global benchmark for high-performance sealing.

1. FKM – Fluoroelastomer (Fluorocarbon Rubber)

FKM (also known as Viton®) was developed during World War II to solve leakage issues caused by nitrile rubber seals in aircraft systems. Thanks to the strong chemical bond between fluorine and carbon (F–C), FKM offers exceptional heat and chemical resistance — ushering in a new era in sealing technology.

By the late 1950s, the first and second generations of FKM were commercialized, with fluorine content increasing from 26.7% to 68%. This advancement significantly improved corrosion resistance and overall stability under harsh environments.

2. Advantages and Limitations of FKM

✅ Key Advantages:

• Wide operating temperature range: -45°C to 204°C

• Excellent resistance to chemicals, ozone, weathering, and flame

• High mechanical strength and low compression set for improved sealing efficiency

• Compatible with CIP and SIP cleaning processes; compliant with FDA standards

• Versatile across industries: automotive, oil & gas, aerospace, and heavy manufacturing

⚠️ Limitations:

• Limited performance in highly aggressive chemical environments

• Not suitable for molten alkalis or gaseous alkali metals

• Higher cost compared to conventional rubbers

• Improper grade selection can lead to rapid seal degradation

3. FFKM – Perfluoroelastomer (The Highest-Performance Elastomer Available)

In the 1960s, the demand for materials with even greater heat and chemical resistance led to the development of FFKM. Combining the chemical durability of PTFE (Teflon®) with the elasticity of FKM, FFKM provides the ultimate sealing solution for the most demanding industrial environments.

DuPont™ Kalrez®, the world’s leading FFKM brand, represents the pinnacle of sealing technology — trusted across industries such as Semiconductor, Electronics, Chemical Processing, Oil & Gas, Solar Energy, Pharmaceutical, and Food & Beverage.
Kalrez® seals are engineered for ultra-high purity, exceptional durability, and stable performance under extreme conditions of chemicals, temperature, and pressure.

4. Advantages and Limitations of FFKM

✅ Superior Advantages:

• Extremely wide operating temperature range: -55°C to 330°C

• PTFE-level chemical resistance – the best among all elastomers

• Self-extinguishing; does not ignite in air

• Ultra-high purity – ideal for semiconductor and pharmaceutical applications

• Excellent mechanical strength for long-term sealing integrity

• Suitable for CIP/SIP processes and FDA-compliant applications

⚠️ Limitations:

• High cost – typically used when other elastomers cannot meet performance requirements

• Larger thermal expansion coefficient – requires careful groove design

• Not compatible with molten alkalis or gaseous alkali metals

5. FFKM vs FKM – Which Should You Choose?

In summary:

• If your application demands extreme resistance to heat, chemicals, and contamination, DuPont™ Kalrez® FFKM is the ultimate choice.

• If you seek a cost-effective balance between performance and price, FKM remains a reliable and efficient solution for most industrial uses.

6. Why Choose Filterfine Vietnam – Authorized Distributor of DuPont™ Kalrez®

Filterfine Vietnam is committed to delivering:

• 100% genuine DuPont™ Kalrez® FFKM products

• In-depth technical consulting and optimized sealing solutions for every application

• Professional service, fast delivery, and strong customer support

Filterfine Vietnam – Official Authorized Distributor of DuPont™ Kalrez® in Vietnam
High-performance sealing solutions – Elevating technology, creating sustainable value.