Buna-N O-Rings Typical Applications and Products
The range of performance characteristics of Buna-N allows it to be utilized in a diverse set of applications. NBR is often used for gaskets and o-rings in pneumatic, hydraulic, and fuel systems.
V-packings and backup rings made from high-hardness Nitrile compounds are common in high-pressure environments in the Oil and Gas industry. The abrasion and wear resistance of NBR make it useful for dynamic oil seals for rotary and reciprocating shafts. NBR is relatively easy to process which keeps costs down for custom extrusions and complex molds. Hardness ranges from 40 Shore A to 90 Shore A. Hydrogenated versions of NBR (HNBR) have enhanced mechanical properties as well as greater thermal and chemical stability.
Specific physical properties and chemical resistances vary by compound formulation.
NBR can be compounded for enhanced oil and fuel resistance, increased temperature flexibility, high hardness, and extrusion resistance, low compression set, and a variety of other attributes. The physical properties of the compound largely depend on the Acrylonitrile content of the formulation.
For example, high Acrylonitrile content causes increased oil and fuel resistance while adversely affecting low-temperature flexibility and compression set resistance. It is important to consider the offsetting attributes when selecting an NBR formulation.