EPDM (ethylene-propylene-diene rubber, typically 70 Shore A) is the water, steam and outdoor-weathering elastomer. Specified on o-ring seal it determines the corrosion behaviour (excellent in water, steam, brake fluid and weathering; unsuitable for mineral oil) and the service temperature range (approx. -45 °C to +150 °C); the dimensions are ours rather than a standard's, and are listed in full below.
Why Choose EPDM for O-Ring Seal — ISO / DIN (Series 159)
The water, steam and outdoor-weathering elastomer. For o-ring seal — iso / din (series 159), this matters when excellent in water, steam, brake fluid and weathering; unsuitable for mineral oil is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ethylene-propylene-diene rubber, typically 70 Shore A |
|---|---|
| Magnetic response | Non-magnetic |
| Service temperature | approx. -45 °C to +150 °C |
| Corrosion characteristic | Excellent in water, steam, brake fluid and weathering; unsuitable for mineral oil |
Corrosion Behavior in Service
Carbon and alloy steel o-ring seal — iso / din (series 159) 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.
Galvanic & Galling Considerations
Galvanic and galling behavior do not apply to o-ring seal — iso / din (series 159) in EPDM — the relevant compatibility questions are chemical: confirm the elastomer against the fluid, the temperature and any cleaning agents in service, and check the gland or groove dimensions give the intended compression on the section.
Sizes of O-Ring Seal — ISO / DIN (Series 159) Available in EPDM
| Inner diameter d1 (mm) | Outer diameter d2 (mm) | Wire dia (mm) | Working temp range | Reference standard |
|---|---|---|---|---|
| 5 | 9 | 2 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 8 | 12 | 2 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 10 | 16 | 3 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 15 | 21 | 3 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 20 | 26 | 3 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 25 | 33 | 4 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 30 | 38 | 4 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 40 | 50 | 5 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 50 | 60 | 5 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 60 | 72 | 6 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 80 | 92 | 6 | -30 to +110 C | ISO 3601 / GB/T 3452 |
| 100 | 114 | 7 | -30 to +110 C | ISO 3601 / GB/T 3452 |
Dimensions are independent of the material: the table above lists the sizes supplied, and on this page every one of them is quoted in EPDM. The catalogue's default material column has been omitted here so it cannot be read as contradicting that.
Custom manufacturing · Made to drawing
Need this seal in a grade that is not listed?
Epdm is one of the grades the catalog describes. Inside diameter, cross-section and compound are the three that matter, and the compound is chosen against the fluid and the temperature rather than the dimensions.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.

