Viton vs EPDM: What’s the Difference?

Viton and EPDM differ in their temperature range, chemical resistance, and flexibility.

In industrial applications, manufacturers often use Viton to handle fuel, oil, and high-temperature environments.

In water-based systems, EPDM makes for a better seal due to its resistance to steam and weather conditions.

Let’s take a closer look at how they compare.

EPDM vs Viton: Key Differences At A Glance

Property	Viton	EPDM
Temperature Range	-20°C to 210°C (-4°F to 410°F)	-45°C to 145°C (-49°F to 293°F)
Chemical Compatibility	Works well with oils, fuels, lubricants, and most acids	Handles water, steam, and mild chemicals but does not resist oil
Durability	Strong, dense, and holds up under pressure	Flexible and tear-resistant but not as tough as Viton
Cost	Costs more	More affordable

Which is Better, EPDM or Viton?

Neither is universally better—it depends on the application and conditions.

For fuel, chemicals, and extreme heat, Viton is the superior choice.

For water, steam, and cold environments, EPDM performs better at a lower cost.

What is Viton Good For?

Viton is best for applications requiring high-temperature resistance and exposure to oils and aggressive chemicals.

It is commonly used in fuel systems, aerospace, automotive, and industrial valves handling harsh fluids.

When Not to Use Viton Seals?

Viton is not ideal for water-based applications, as it does not hold up well in steam or hot water environments.

It also becomes stiff and loses flexibility in cold conditions below -20°C (-4°F).

What are the Disadvantages of Viton?

Viton is expensive and may not be necessary for applications that do not require oil or chemical resistance.

It also lacks flexibility in freezing temperatures and is not suited for water-heavy systems.

Viton Chemical Compatibility

Viton resists a wide range of aggressive chemicals, including oils, fuels, and acids.

However, it does not work well with steam, water, or glycol-based fluids.

EPDM Seal Applications

EPDM is widely used in water treatment, irrigation, and steam applications due to its resistance to water and aging.

It is also common in outdoor seals, roofing materials, and automotive weatherproofing.

Alternative Seal Materials: PTFE and NBR

While Viton and EPDM are popular choices, other seal materials are available for different applications.

• PTFE (Teflon) is highly resistant to chemicals, has low friction, and is often used in food-grade and corrosive applications.
• NBR (Nitrile Rubber) is a great option for applications involving petroleum-based oils and fuels but does not perform well with water or steam.

Viton vs. EPDM in Valve Design

Viton and EPDM seals are used in different types of valves based on material compatibility and performance needs.

Ball valves, which control flow by rotating a ball inside the valve body, often use Viton seals in oil, fuel, and chemical applications.

Diaphragm valves, which use a flexible membrane to regulate flow, typically rely on EPDM for water and steam applications.

Globe valves, designed for precise flow control, often incorporate Viton for high-pressure fuel systems and EPDM for steam-based operations.

Final Thoughts

At the end of the day, choosing the right seal comes down to what works best for your system.

Viton is built for fuel, oil, and high heat, while EPDM handles water, steam, and the outdoors.

Other options, like PTFE and NBR, fill specific needs where flexibility and durability matter most.

If you’re unsure which material fits your project, talk to a supplier or manufacturer to get the best match for your needs.

Reference

Guide to Valve Seal Materials: Viton, PTFE, NBR, and EPDM