Buna N and Viton are two common types of elastomers, which are used in a variety of applications, including sealing, gasketing, and o-rings. While both materials are popular choices for these applications, they have different properties and characteristics that make them suitable for different environments and conditions.
Buna N, also known as nitrile rubber, is a synthetic rubber material that is known for its excellent resistance to oil, fuel, and other petroleum-based fluids. Buna N is also resistant to water, hydraulic fluids, and most chemicals, making it a popular choice for applications in the automotive, aerospace, and industrial industries.
One of the advantages of Buna N is its affordability. Compared to other elastomers, Buna N is relatively low-cost, which makes it an attractive choice for applications where cost is a major factor. Buna N is also easy to process and has good physical properties, including high tensile strength and good abrasion resistance.
However, Buna N has some limitations. It has poor resistance to ozone, sunlight, and weathering, which can cause it to break down and degrade over time. It also has limited resistance to high temperatures, with a maximum continuous operating temperature of around 250°F (120°C). Additionally, Buna N is not recommended for use in applications that involve exposure to aromatic hydrocarbons, ketones, or esters, as these chemicals can cause it to swell or degrade.
Viton, on the other hand, is a fluorocarbon elastomer that is known for its exceptional chemical resistance and high-temperature performance. Viton is resistant to a wide range of chemicals, including acids, alkalis, fuels, and solvents, and can operate at temperatures up to 400°F (200°C).
One of the primary advantages of Viton is its outstanding resistance to powerful chemicals, making it an ideal choice for applications in the chemical processing and oil and gas industries. Viton also has excellent resistance to ozone, weathering, and sunlight, allowing it to maintain its properties and performance over long periods.
However, Viton is more expensive than Buna N, which makes it less suitable for applications where cost is an major consideration. Viton is also more difficult to process than Buna N, which can make it more challenging to manufacture parts and components.
In summary, while both Buna N and Viton are popular choices for sealing, gasketing, and o-ring applications, they have different properties and characteristics that make them suitable for different environments and conditions. Buna N is an affordable and versatile material that is ideal for applications that involve exposure to oil, fuel, and hydraulic fluids. Viton, on the other hand, is a premium material that offers exceptional chemical resistance and high-temperature performance, making it ideal for use in aggressive chemical environments and high-temperature applications. Ultimately, the choice between Buna N and Viton will depend on the specific requirements of the application, including the type of fluid or chemical involved, the temperature range, and the budget for the project.