Harltex FKM Rubber VIT700

Why Harltex VIT700 Is the Future of High-Performance Engineering
In industries where extreme environments push materials to their limits, FKM rubber (fluoroelastomer, commonly known as Viton®) has earned its reputation as a premium solution. More than just a sealing compound, Harltex FKM – VIT700 is an advanced elastomer engineered to perform in conditions where conventional rubbers cannot survive.
What Makes FKM Unique?
Fluoroelastomers (FKM) are a family of synthetic rubbers containing a high fluorine content. As a result, this molecular structure gives FKM exceptional resistance to:
- Heat – continuous use up to 200°C, with short-term peaks beyond.
- Chemicals – hydrocarbons, oils, fuels, acids, and aggressive solvents.
- Environment – ozone, UV light, and oxidative ageing.
Unlike general-purpose rubbers like EPDM or NBR, FKM maintains its properties across a much broader operating window. Consequently, it has become indispensable in demanding engineering applications.
The Performance of Harltex VIT700
Harltex FKM – VIT700 compound has been independently tested to ASTM standards, therefore confirming its suitability as a high-performance engineering material:
- Mechanical Strength: Tensile strength of 18.2 MPa and elongation of 195%, ensuring both durability and flexibility.
- Thermal Stability: Excellent compression set results (17% after 24h @ 200°C), retaining shape and resilience under prolonged heat exposure.
- Chemical Resistance: Minimal property changes after immersion in fuels, oils, and service fluids.
Environmental Endurance: Ozone resistance testing showed no surface cracks, further proving long-term durability in outdoor or oxidising conditions.
Beyond Sealing: Wider Applications for FKM
While O-rings and gaskets are the most common uses of FKM, VIT700 is a material suited to much broader applications. For example:
- Automotive – hoses, diaphragms, and fuel system components.
- Aerospace – fluid transfer systems, engine components, and insulation materials.
- Industrial Processing – chemical-resistant linings, expansion joints, and valve components.
- Energy & Oil/Gas – seals, packers, and parts exposed to aggressive hydrocarbons and sour gas.
- Consumer Products – high-performance rubber parts in electronics and appliances requiring heat and chemical resistance.
Therefore, VIT700 is not confined to sealing—it is a versatile material across multiple sectors.
Why Choose Harltex FKM – VIT700?
At Harltex, we’ve combined decades of expertise in engineered rubber with the latest material science. As a result, VIT700 is not just another FKM—it’s a carefully developed compound that provides a balance of strength, resilience, and resistance across multiple environments.
Ultimately, by choosing VIT700, manufacturers gain confidence in a material that performs consistently, reduces failure rates, and extends service life in critical applications.
Harltex FKM – VIT700 is more than a sealing material—it is a versatile, high-performance elastomer designed for the most demanding industries. Whether in aerospace, automotive, industrial processing, or energy, VIT700 offers a proven combination of mechanical integrity, chemical resistance, and thermal stability.
⬇ Download the full Harltex FKM – VIT700 Brochure and Technical Data Sheet and discover how this advanced material can elevate your products and processes.
For more information about our products , contact the experts at Harltex today, and let us bring precision and high-performance to your next project.
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