China Nitrile/NBR O-Ring Manufacturer with Competitive Pricing & Superior Quality
- Payment Way: T/T, Western Union, Paypal
- Incoterm: EXW, FOB, CIF
- Shipping Way: By Air or Sea
- Manufacturer Place: Ningbo, China
- Delivery Time: 7 - 30 days
- Factory Status: Stocked for Sale
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Description
NBR O-Rings, also known as Nitrile O-Rings, Buna-N O-Rings, or Perbunan O-Rings, are general‑purpose O-shaped sealing rings made from the copolymer of butadiene and acrylonitrile. They deliver an excellent balance of mechanical properties, oil resistance, and cost‑effectiveness, making them highly reliable for daily industrial sealing requirements.
Because of their affordable cost and well‑balanced performance, they are the most widely used rubber O-rings in the world. It is estimated that NBR O-rings currently account for 40% to 60% of rubber O-ring usage in industrial applications, particularly in automotive systems, hydraulic equipment, fuel handling systems, and general mechanical engineering.
These seals are manufactured through the copolymerization of acrylonitrile and butadiene, with acrylonitrile content typically ranging from 18% to 50%. Increasing the acrylonitrile content enhances resistance to petroleum-based hydrocarbon fuels and oils, though it concurrently reduces low-temperature flexibility.
Specifications
- Material: NBR / Nitrile / Buna-N / Perbunan
- Temperature Range / Rating: -40 °C (-40 °F) to 120°C (248 °F)
- Low Operating Temperature Limit: -40 °C (-40 °F)
- Maximum Operating Temperature Limit: 120°C (248 °F)
- Durometer Hardness Range: Shore A 50-90
- Standard Durometer Hardness: Shore A 70
- Less Used Duro Hardness: Shore A 50, 60, 90
- Color: Black (standard), custom color is available
- Outline: Round, square, rectangular, custom
- Cross Section Profile: Round (standard), square, X, D, T, custom
- Cross Section Width (CS): 0.5 to 20 mm (0.020 to 0.787 inch)
- Inside Diameter (ID): 0.7 to 2965 mm (0.028 to 116.732 inch)
- Standard Size: AS 568, BS 1806, ISO 3601, DIN 3771, JIS B 2401
- Shelf Life: 5 – 7 years
- Compliance: RoHS, REACH, FDA (available upon request)
- Price Level: Low
Performance Characteristics
The chart below summarizes the typical resistance characteristics of standard Nitrile (NBR) rubber to common media and environmental factors. Ratings are based on industry-standard evaluations: Excellent (recommended), Good (suitable with limitations), Fair (limited use), and Poor (not recommended).
Excellent
- Oils
Good
- Water
- Abrasion
- Compression Set
- Tensile Strength
Fair
- Weather
- Chemicals
- Acids
- Alkali
- Steam
Poor
- Ozone
- Flame
Material Data Sheet
The following table presents the physical properties and fluid resistance performance of our standard Nitrile (NBR) O-ring material, formulated to meet ASTM D2000 M2BG714 specifications. All test results are based on cured compounds tested per the indicated ASTM methods, including heat aging, compression set, water immersion, and exposure to Fuel A, Fuel B, Oil No. 1, and Oil No. 3.
This is the Material Data Sheet (MDS) for our standard 70 Shore A NBR compound. Savvy Rubber also offers and routinely tests 50, 60, 80, and 90 Shore A NBR formulations. If you require data for other hardness grades, please contact our sales team.
| Savvy Rubber NBR Shore A 70 Material Data Sheet | |||
|---|---|---|---|
| Test Standard: ASTM D2000 M2BG714 A14 B14 EA14 EF11 EF21 EO14 EO34 F19 | |||
| ORIGINAL PHYSICAL PROPERTIES | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Hardness Shore A | D2240 | 70±5 | 72 |
| Tensile Strength, MPa (psi) | D412 | 14 (2031) min. | 19 (2755) |
| Ultimate Elongation, ％ | 250 min. | 300 | |
| Specific Gravity (g/cm³) | D792 | — | 1.22 |
| HEAT RESISTANCE 70H AT 100℃ (A14) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Hardness Change, Points | D573 | -15 to +15 | +5 |
| Tensile Strength Change, % | -30 max. | -8 | |
| Ultimate Elongation Change, % | -50 max. | -12 | |
| COMPRESSION SET, 22H AT 100℃ (B14) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Permanent Set % | D395 | 25 max. | 18 |
| WATER RESISTANCE, 70H AT 100℃ (EA14) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Hardness Change, Points | D471 | -10 to +10 | +3 |
| Volume Change, % | -15 to +15 | +5 | |
| FLUID RESISTANCE, FUEL A, 70H AT 23℃ (EF11) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Hardness Change, Points | D471 | -10 to +10 | +5 |
| Tensile Strength Change, % | -25 max. | -3 | |
| Ultimate Elongation Change, % | -25 max. | -8 | |
| Volume Change, % | -5 to +10 | -1 | |
| FLUID RESISTANCE, FUEL B, 70H AT 23℃ (EF21) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Hardness Change, Points | D471 | 0 to -30 | -6 |
| Tensile Strength Change, % | -60 max. | -22 | |
| Ultimate Elongation Change, % | -60 max. | -21 | |
| Volume Change, % | 0 to +40 | +26 | |
| FLUID RESISTANCE IRM 901 OIL, 70H AT 100℃ (EO14) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Hardness Change, Points | D471 | -5 to +10 | +7 |
| Tensile Strength Change, % | -25 max. | -16 | |
| Ultimate Elongation Change, % | -45 max. | -21 | |
| Volume Change, % | -10 to +5 | -7 | |
| FLUID RESISTANCE IRM 903 OIL, 70H AT 100℃ (EO34) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Hardness Change, Points | D471 | -10 to +5 | -6 |
| Tensile Strength Change, % | -45 max. | -11 | |
| Ultimate Elongation Change, % | -45 max. | -13 | |
| Volume Change, % | 0 to +25 | +17 | |
| LOW TEMPERATURE RESISTANCE (F19) | TEST METHOD | REQUIREMENTS | TEST RESULTS |
| Non-brittle after 3 Min at -40°C | D2137 | PASS | PASS |
Test results are typical values for Savvy Rubber standard Shore A 70 NBR compound. Actual performance may vary based on operating conditions, fluid concentration, and exposure time. For critical applications, we recommend sample testing.
Features
Nitrile / NBR O-rings are the most widely used sealing material in industrial applications because they offer strong resistance to oils, fuels, and greases at a very low cost. They work reliably between –40°C and +120°C, provide good mechanical strength, and are suitable for both static and low-speed dynamic sealing applications.
However, NBR has limited resistance to ozone, sunlight, and weathering, and it performs poorly in contact with ketones, esters, chlorinated solvents, and glycol-based brake fluids (DOT 3/4). It is also not suitable for high-temperature applications above +120°C.
For applications involving aggressive chemicals, high temperatures, or ozone-rich environments, consider alternative materials such as FKM (Viton®), HNBR, or EPDM.
Applications
Buna-N / NBR o-rings are widely used in applications that require reliable sealing against oils, fuels, and greases. They are commonly found in automotive fuel systems, hydraulic equipment, and industrial machinery, where exposure to petroleum-based hydraulic oil, gasoline, silicone oil, diester lubricants, and glycol-based fluids is typical. Their strong resistance to these media makes them the preferred choice for seals in fuel tanks, oil reservoirs, pumps, valves, and transmission systems across a range of industries.
