Seals are essential components in various industrial applications to prevent fluid or gas leakage and protect against environmental elements. Due to their advantageous properties, Viton and Buna are two of the most commonly used elastomers for sealing. They offer excellent resistance to compression sets and are compatible with most oils and lubricants, particularly petroleum-based substances.
In this article, we will examine the features, advantages, and applications of Viton and Buna seals. We will also list their characteristics to help you choose the best option for your sealing needs.
Viton seals are rubber seals composed of the fluoroelastomer substance Viton. Their tolerance to fuels, oils, and chemicals makes them a go-to choice for chemically resistant sealing applications. Moreover, they are distinguished for their superior performance in high-temperature and corrosive environments.
Here are some of Viton gaskets’ most advantageous characteristics:
- Durometer range of 60 to 90
- Excellent heat and sunlight stability
- Exceptional resistance to oxidation, UV exposure, weather, fungi, and mold
- Maximum elongation of 300%
- Superior abrasion and tear resistance
- Temperature range of 400 °F (204 °C) to 600 °F (315 °C)
- Tensile range of 500 to 2000 psi
Due to their unique properties and benefits, Viton seals have a wide range of applications, including the following:
- Aerospace (fuel systems, hydraulic systems, valves, and seals)
- Automotive (engine systems and transmission)
- Chemical processing (pumps and valves)
- Food processing (pumps, valves, filling machines, and sealers)
- Industrial machinery (seals, pumps, and motors)
- Oil and gas (pipelines)
Buna seals — often referred to as Nitrile, Buna-N, Perbunan, or NBR — are made from a copolymer of butadiene and acrylonitrile. As they are constructed from a cheaper substance, one of Buna’s advantages over Viton is its cost-effectiveness. Additionally, they are more flexible at low temperatures and have a better compression set resistance.
Other characteristics of Buna seals are listed below:
- Durometer range of 20 to 95
- Excellent resistance to abrasion
- Exceptional resistance to oil, fuels, chemicals, and heat aging
- Good adhesion to metals
- Maximum elongation of 600%
- Temperature range of -30 °F (-34 °C) to 250 °F (121 °C)
- Tensile range of 200 to 3000 psi
Despite not being as universally resistant to chemicals, weather, and ozone exposure as Viton, Buna seals offer versatility. This makes them suitable for heavy-duty industrial applications, including the following:
- Automotive and aircraft manufacturing (fuel and oil systems)
- HVAC (compressors, expansion valves, duct works, and refrigerant lines)
- Industrial machinery (hydraulic and pneumatic systems)
- Marine (fuel systems)
- Oil and gas (pipelines and storage tank seals)
- Pharmaceutical (storage tank seals, processors, and conveyor systems)
High-Quality Seals From Custom Gasket Manufacturing
Viton and Buna are alternative sealing materials with a wide range of applications. Nonetheless, weighing the benefits, drawbacks, and specific purposes of the two is crucial to optimize your selection.
Custom Gasket Manufacturing specializes in precision rubber gaskets and seals for multiple applications and industries, including Buna and Viton gaskets in various grades! We have a team of experts who can help you select the optimal sealing product for your project. In addition, we provide commercial-grade and specification-grade materials that meet FDA and ASTM requirements, ensuring high-quality seals.