How to make the right decision when it comes to FKM O-Rings

February 24, 2023 – by Eastern Seals

FKM o-rings, also known as Viton® o-rings are made of fluoroelastomer, which is an extremely resilient and hard-wearing form of synthetic rubber. This makes FKM o-rings an ideal choice for aggressive chemicals and fuels that would quickly degrade other rubbers.

However, it’s important to note that all FKMs are not made equal. If you are looking for the best FKM o-rings, you need Viton® o-rings.

In this post, we share tips on making an informed decision when it comes to FKM o-rings.

What are Viton® o-rings?

Viton® is the trade name for the Chemours brand of fluorocarbon, which was originally developed by DuPont in 1958. FKM refers to a family of fluorocarbon-based fluoroelastomer materials as defined by ISO standard 1629 and ASTM International standard D1418.

Fluorocarbon is commonly known in the industry as FKM, and Chemours is not the only manufacturer of FKM products, and that’s the cause for all confusion. Just because an o-ring has been made using FKM does not mean it has been made using Viton® FKM. There’s a huge difference between generic FKM and genuine Viton® FKM o-rings.

Generic FKM o-rings vs genuine Viton® o-rings

Although the terms Viton® and FKM are used interchangeably, they are not the same.

O-rings and sealants that are not made using 100% virgin Chemours Viton® may not meet the stringent quality and performance standards set by Chemours for Viton®.

Both materials also differ in their curing process.

While generic FKM o-rings are bisphenol-cured, FKM o-rings whith peroxide-cured offer better acid solution resistance compared to bisphenol-cured.

In some applications, adding a few organic amines or amides or using peroxide-cured Viton® FKM o-rings will deliver better results than bisphenol-curing systems.

We are one of the UK’s leading suppliers of FKM o-rings. With expertise in sealing solutions for varied sectors, we can cater to every requirement with our customised solutions. Shop online or click here to request a quote!