A4 Stainless Steel O-Ring Seal are stocked to ISO / DIN. The grade provides superior, including marine and chloride environments and is largely non-magnetic; the practical service range is approx. -200 °C to +400 °C. Property data, grade comparison and the full size table follow.
Why Choose A4 Stainless Steel for O-Ring Seal — ISO / DIN (Series 159)
Specified for marine, coastal and chemical applications. For o-ring seal — iso / din (series 159), this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A4-80 (316) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Superior, including marine and chloride environments |
Corrosion Behavior in Service
A4 (316) adds 2–3% molybdenum to the A2 (304) composition, which dramatically improves resistance to chloride-pitting corrosion. For O-Ring Seal — ISO / DIN (Series 159) in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Galvanic & Galling Considerations
Two important notes for stainless o-ring seal — iso / din (series 159): (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Sizes of O-Ring Seal — ISO / DIN (Series 159) Available in A4 Stainless Steel
| 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 |