Nitrile (Buna-N) Rubber Washers — Complete Guide
Nitrile rubber, also known as Buna-N or NBR, is the industry standard for oil and fuel resistance. If your application involves petroleum products, hydraulic fluid, or mineral oils, nitrile rubber washers are almost always the correct choice.
Nitrile Washer Properties
- Temperature range: -40°F to +250°F (-40°C to +121°C)
- Oil and fuel resistance: Excellent — best of common rubbers
- Hydraulic fluid resistance: Excellent
- Weather/ozone resistance: Poor — not for outdoor use
- Water resistance: Good
Best Applications for Nitrile Washers
- Automotive fuel systems and carburetors
- Hydraulic equipment and machinery
- Oil and gas fittings
- Industrial machinery with lubricant contact
- Compressors and pumps
When Not to Use Nitrile
Avoid nitrile in outdoor or UV-exposed applications — it degrades quickly. For outdoor use, choose EPDM or Neoprene. For extreme chemical resistance, use Viton.