Material specification page for o-ring seal in NBR (Nitrile). Covers the grade designation (acrylonitrile-butadiene rubber, typically 70 Shore A), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to ISO / DIN.
Why Choose NBR (Nitrile) for O-Ring Seal — ISO / DIN (Series 160)
The default elastomer for oil and hydraulic sealing. For o-ring seal — iso / din (series 160), this matters when good resistance to mineral oil, grease and hydraulic fluid; poor in ozone and weathering is the primary requirement.
Mechanical & Physical Properties
| Grade designation | acrylonitrile-butadiene rubber, typically 70 Shore A |
|---|---|
| Magnetic response | Non-magnetic |
| Service temperature | approx. -30 °C to +100 °C |
| Corrosion characteristic | Good resistance to mineral oil, grease and hydraulic fluid; poor in ozone and weathering |
Corrosion Behavior in Service
Carbon and alloy steel o-ring seal — iso / din (series 160) require a coating for corrosion protection. Zinc plating (with or without passivation) is the most common; hot-dip galvanizing is used for outdoor structural service; black-oxide is mainly a tarnish-prevention finish for tool-room use.
Comparable Grades
For o-ring seal — iso / din (series 160), consider FKM where temperature or chemical exposure is higher, or EPDM where the medium is water, steam or brake fluid rather than oil. Elastomer selection is decided by the medium, the temperature range and whether the seal is static or dynamic — not by strength.
Sizes of O-Ring Seal — ISO / DIN (Series 160) Available in NBR (Nitrile)
| Inner diameter d1 (mm) | Outer diameter d2 (mm) | Wire dia (mm) | Material | Working temp range | Reference standard |
|---|---|---|---|---|---|
| 5 | 9 | 2 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 8 | 12 | 2 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 10 | 16 | 3 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 15 | 21 | 3 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 20 | 26 | 3 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 25 | 33 | 4 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 30 | 38 | 4 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 40 | 50 | 5 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 50 | 60 | 5 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 60 | 72 | 6 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 80 | 92 | 6 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 100 | 114 | 7 | NBR 70 | -30 to +110 C | ISO 3601 / GB/T 3452 |

