Buna-N (NBR) O-Rings
Buna-N, also known as Nitrile or NBR, is one of the most widely used elastomer compounds for O-Rings. Acrylonitrile-butadiene, the formal name for Buna, is available in standard durometers of 70 and 90 but can be produced in other hardness levels as well.
Standard Durometer & Colors
These O-Rings are typically black. Known for being cost-effective and readily available, Buna-N O-Rings come in a vast array of sizes.
Temperature Range for Buna O-Rings
Buna has a temperature range of -30°F to 250°F.
Recommended Uses for Buna-N (NBR) O-Rings:
- Silicone Greases and Oils
- Water
- Petroleum Oils
- Fuels
Not Recommended For:
- Ketones
- Halogenated Hydrocarbons
- Auto and Aircraft Glycol-based Brake Fluids
- Strong Acids
- Applications that are not resistant to sunlight, ozone, or weathering
Benefits of Buna (Nitrile):
- Good wear resistance
- Good compression set resistance
- Good short-term resilience
- Good permeation resistance
Common Applications for Buna
- Hydraulic Oils and Fuels
- Extreme Service-life
- Pneumatic
- Vacuum
Our extensive inventory includes standard and metric size O-rings, quad-rings, backup rings, and other parts. For unique or hard-to-find sizes or shapes, we will collaborate with our manufacturing partners to source the exact seal you need.
For additional technical information on Buna-N (NBR) O-rings and other materials, including chemical compatibility, resistance to abrasion, suitability for dynamic or static applications, temperature operating ranges, and longevity, visit our Technical Information pages.