Materials → Nitrile (NBR)
Material profile · 03/06
NITRILE (NBR)
The cost-effective standard elastomer for mineral-oil hydraulic systems.
- -30°C to 100°C
- Temp. range
- 70-90 Shore A
- Hardness
- Medium
- Friction
- Very good
- Oil resistance
Overview
Where Nitrile (NBR) earns its place.
Nitrile rubber is the baseline elastomer across hydraulic sealing because it resists mineral oils and standard hydraulic fluids at a moderate cost. It is moulded into O-rings, backup rings, piston seals, and rotary seal lips wherever the operating fluid and temperature sit inside its comfort zone. NBR is not the material to specify for outdoor UV exposure or aggressive synthetic fluids, but for enclosed mineral-oil systems running at conventional temperatures, it remains the most economical, readily available option.
Used in
Best-fit industries
Trade-offs
Advantages and limitations.
Advantages
- Strong resistance to mineral oils and standard petroleum-based hydraulic fluids.
- Lowest material cost of the common sealing elastomers.
- Wide availability across hardness grades and standard O-ring sizes.
- Good general-purpose compression set and elasticity.
Limitations
- Poor resistance to ozone, UV, and outdoor weathering over time.
- Not suited to aggressive synthetic fluids or high-temperature continuous duty.
- Swells or degrades in contact with many solvents and some biodiesel blends.
Operating envelope
Typical technical reference.
Figures are typical for the compound family and vary by specific grade and cure. Confirm exact limits against your fluid, pressure, and duty cycle before finalising a specification.
| Operating temperature | -30°C to 100°C (up to 120°C for select grades) |
| Typical hardness | 70-90 Shore A |
| Friction coefficient | Medium |
| Fluid compatibility | Mineral oils, standard hydraulic fluids |
| Duty type | Static and dynamic — O-rings, piston, rotary |
Compare
See the other five materials.
Engineering support
Confirm if Nitrile (NBR) is right for your application.
Share the product family, dimensions, pressure, temperature, media, drawing, or sample photo. Fitofit will confirm the right material direction.