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NBR (Nitrile Rubber) is a synthetic rubber made from the copolymerization of butadiene and acrylonitrile, while FKM (Fluoroelastomer) is a high-performance synthetic rubber made from the copolymerization of fluorine-containing monomers. Our factory produced O-ring such as 702-21-55890 contains a variety of materials for you to choose.
Oil Resistance:
NBR O-rings perform well in conventional oils, while FKM O-rings perform better in more severe oils and chemicals.FKM O-Rings perform better in more severe oils and chemicals, and are more resistant to certain organic solvents.
Temperature resistance:
FKM is better in high temperature resistance, general use temperature range: -20~250℃, NBR is better in cold resistance, generally applicable to -30℃~100℃.
Chemical resistance:
FKM can resist more kinds of chemical media such as a variety of acids, alkalis, salts and other chemicals, NBR chemical resistance but less resistance to ketone solvents.
Price: In general, the cost of FKM is higher than that of NBR, mainly due to its higher production cost and strict technical requirements. However, in specific high-performance applications, its performance advantages can offset the cost difference.
To summarize
When choosing between NBR O-rings or O-rings made of FKM, if the application involves severe conditions such as high temperatures and chemical corrosion, FKM may be the more appropriate choice. For general industrial applications, NBR may be the more economical choice. No matter which material, we have production such as ZD12P01500, etc., welcome to inquire.
