Key specifications
- Material
- NBR 70 Shore A, black
- Inner diameter
- 1 – 659 mm
- Cross-section
- 1 / 1.1 / 1.2 / 1.42 / 1.5 / 1.6 / 1.63 / 1.65 / 1.67 / 1.78 / 1.83 / 1.9 / 1.98 / 2 / 2…
- Standard sizes
- 2,900+
Selected size:
Product Description
The most widely used general-purpose O-ring for mineral oil, grease and water in hydraulic and pneumatic systems. 2,900+ standard sizes available. For a quote, please send the inner diameter × cross-section, material and quantity.
Technical Specifications
| Material | NBR 70 Shore A, black |
|---|---|
| Inner diameter | 1 – 659 mm |
| Cross-section | 1 / 1.1 / 1.2 / 1.42 / 1.5 / 1.6 / 1.63 / 1.65 / 1.67 / 1.78 / 1.83 / 1.9 / 1.98 / 2 / 2.2 / 2.4 / 2.46 / 2.5 / 2.62 / 2.95 / 3 / 3.5 / 3.53 / 4 / 4.5 / 5 / 5.33 / 5.7 / 6 / 6.99 / 8 / 8.4 / 8.6 / 10 mm |
| Standard sizes | 2,900+ |
Material and operating conditions
| Elastomer | NBR (nitrile butadiene rubber) |
|---|---|
| Hardness | 70 ± 5 Shore A |
| Colour | Black |
| Operating temperature | -30 °C … +100 °C (short-term +120 °C) |
| Suitable media | Mineral-oil hydraulic fluids, greases, water (up to about +80 °C), compressed air |
| Not suitable for | Glycol-based brake fluids, ketones, esters, aromatic and chlorinated hydrocarbons, ozone and long-term outdoor weathering |
| Pressure | Up to about 100 bar without a back-up ring in static applications with tight clearances; use a back-up ring or NBR 90 for higher pressure |
Size standard
| Size designation | Inner diameter (d1) × cross-section (d2), mm |
|---|---|
| Standards | ISO 3601 metric sizes and AS568 inch-series sizes |
| Cross-section equivalents (AS568) | 1.78 mm = 0.070″ · 2.62 mm = 0.103″ · 3.53 mm = 0.139″ · 5.33 mm = 0.210″ · 6.99 mm = 0.275″ |
ⓘ Values are typical; exact values depend on the manufacturer and compound. Consult our team for critical applications.
Size Table
This product is available in 2,997 standard sizes. The table shows how they are distributed; use the size finder to see every size.
| Cross-section d2 (mm) | Inner diameter d1 (mm) – range | Sizes |
|---|---|---|
| 1 | 1 – 50 | 72 |
| 1.1 | 14 | 1 |
| 1.2 | 2.9 – 4 | 4 |
| 1.42 | 4.7 | 1 |
| 1.5 | 1 – 82 | 103 |
| 1.6 | 3.1 – 37.1 | 32 |
| 1.63 | 7.65 | 1 |
| 1.65 | 10 | 1 |
| 1.67 | 65.4 | 1 |
| 1.78 | 1.78 – 225 | 81 |
| 1.83 | 10.52 | 1 |
| 1.9 | 2.4 – 78.2 | 24 |
| 1.98 | 11.89 | 1 |
| 2 | 1 – 190 | 195 |
| 2.2 | 12 – 15 | 2 |
| 2.4 | 2.2 – 93.2 | 116 |
| 2.46 | 17.93 – 19.18 | 2 |
| 2.5 | 3 – 145 | 120 |
| 2.62 | 1.24 – 349.25 | 94 |
| 2.95 | 21.92 – 80 | 7 |
| 3 | 2 – 495 | 319 |
| 3.5 | 83 | 1 |
| 3.53 | 4.34 – 456.06 | 121 |
| 4 | 4 – 580 | 306 |
| 4.5 | 20 – 230 | 41 |
| 5 | 5 – 590 | 200 |
| 5.33 | 10.46 – 658.88 | 114 |
| 5.7 | 28.93 – 588.6 | 300 |
| 6 | 6 – 590 | 296 |
| 6.99 | 31.12 – 658.88 | 115 |
| 8 | 34 – 514 | 85 |
| 8.4 | 149.5 – 399.5 | 41 |
| 8.6 | 42.8 – 582.8 | 104 |
| 10 | 30 – 600 | 95 |
🔎 Size finder
Applications
- Static and dynamic sealing in hydraulic cylinders, valves and pumps
- Pneumatic cylinders and valves
- Static sealing of flanges, covers and connection faces
- Lubrication and water circuits, gearboxes
- General machine maintenance and repair
Information Needed for a Quote
- Inner diameter × cross-section (mm) or AS568 number
- Material and hardness (e.g. NBR 70)
- Quantity
- Operating conditions: fluid, temperature and pressure
- Static or dynamic (moving) application
Selection and Usage Notes
- Choose FKM (Viton) O-rings for high temperatures or chemical media.
- Use NBR 90 or a back-up ring against extrusion in high-pressure dynamic applications.
- Protect the O-ring from sharp edges and threads during assembly; lubricate it with the system fluid before fitting.
- Choose suitably certified material for food and drinking-water applications.
Frequently Asked Questions
Can you supply a size that is not in the list?
Yes. For non-standard sizes and other materials, request a quote with the size and quantity.
What is the difference between NBR 70 and NBR 90?
NBR 90 is harder and resists extrusion better at high pressure. NBR 70 gives good sealing and easy fitting in general-purpose use.
How is an O-ring size specified?
As inner diameter (d1) × cross-section (d2) in millimetres, for example 25 × 3 mm.
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