FFKM 95 vs. NBR 70

Attribute	FFKM 95	NBR 70
Material Type	FFKM	NBR
Hardness	95 Shore A	70 Shore A
Temperature Resistance	High	Medium
Chemical Resistance	Excellent	Good
Compression Set	Low	Medium

Introduction

When it comes to choosing the right material for sealing applications, two popular options are FFKM 95 and NBR 70. Both materials have their own unique attributes that make them suitable for different environments and conditions. In this article, we will compare the key characteristics of FFKM 95 and NBR 70 to help you make an informed decision for your specific sealing needs.

Chemical Resistance

One of the most important factors to consider when choosing a sealing material is its chemical resistance. FFKM 95, also known as perfluoroelastomer, is highly resistant to a wide range of chemicals, including acids, bases, solvents, and fuels. This makes it an ideal choice for applications where exposure to harsh chemicals is a concern. On the other hand, NBR 70, or nitrile rubber, has good resistance to oils, greases, and hydrocarbons, but is not as resistant to acids and bases as FFKM 95.

Temperature Range

Another important consideration when selecting a sealing material is its temperature range. FFKM 95 has an impressive temperature range, with the ability to withstand temperatures as high as 327°C (620°F) and as low as -26°C (-15°F). This makes it suitable for high-temperature applications where other materials may fail. NBR 70, on the other hand, has a lower temperature range, with a maximum temperature of around 121°C (250°F) and a minimum temperature of -40°C (-40°F). While NBR 70 may not be suitable for extreme temperature conditions, it is still a versatile material for a wide range of applications.

Compression Set

Compression set refers to the ability of a material to return to its original shape after being compressed. FFKM 95 has excellent compression set resistance, maintaining its sealing properties even after prolonged compression. This makes it a reliable choice for applications where consistent sealing performance is crucial. NBR 70, on the other hand, has a moderate compression set resistance, which may lead to decreased sealing effectiveness over time. However, with proper design and maintenance, NBR 70 can still provide reliable sealing performance in many applications.

Hardness

The hardness of a sealing material is another important factor to consider, as it can impact the material's ability to withstand pressure and deformation. FFKM 95 is a relatively hard material, with a durometer hardness of 95 Shore A. This hardness gives FFKM 95 excellent resistance to deformation under pressure, making it suitable for high-pressure sealing applications. NBR 70, on the other hand, has a lower durometer hardness of 70 Shore A, which may make it more prone to deformation under pressure. However, the softer nature of NBR 70 can also provide better sealing performance in certain applications where flexibility is required.

Abrasion Resistance

Abrasion resistance is an important attribute for sealing materials that are exposed to wear and friction. FFKM 95 has excellent abrasion resistance, making it suitable for applications where the seal may come into contact with abrasive materials. The durable nature of FFKM 95 allows it to maintain its sealing properties even in harsh conditions. NBR 70, on the other hand, has good abrasion resistance but may not be as durable as FFKM 95 in high-wear environments. It is important to consider the level of abrasion resistance required for your specific application when choosing between FFKM 95 and NBR 70.

Conclusion

In conclusion, both FFKM 95 and NBR 70 have their own unique attributes that make them suitable for different sealing applications. FFKM 95 offers superior chemical resistance, temperature range, compression set resistance, hardness, and abrasion resistance, making it an ideal choice for high-performance sealing applications. NBR 70, on the other hand, provides good resistance to oils and greases, moderate temperature range, moderate compression set resistance, and good abrasion resistance, making it a versatile option for a wide range of sealing applications. Ultimately, the choice between FFKM 95 and NBR 70 will depend on the specific requirements of your sealing application and the environmental conditions it will be exposed to.