Material specification page for wire rope in Grade 12.9 Steel. Covers the grade designation (class 12.9), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to ISO / DIN.
Why Choose Grade 12.9 Steel for Wire Rope — ISO / DIN (Series 152)
The highest common strength class, for high-load machine assembly. For wire rope — iso / din (series 152), this matters when requires plating or black-oxide protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | class 12.9 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | up to approx. +300 °C |
| Corrosion characteristic | Requires plating or black-oxide protection |
Corrosion Behavior in Service
Carbon and alloy steel wire rope — iso / din (series 152) 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 Wire Rope — ISO / DIN (Series 152), class 8.8 is the comparable strength step. Move up when the joint preload approaches the proof load of the current class; move down when the joint is over-specified. For corrosion-critical service, switch to stainless A2 or A4.
Sizes of Wire Rope — ISO / DIN (Series 152) Available in Grade 12.9 Steel
| Nominal diameter (mm) | Construction | Min breaking force (kN) | Mass (kg/100m) | Material | Reference standard |
|---|---|---|---|---|---|
| 4 | 6x7 | 8.95 | 5.85 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 5 | 6x7 | 13.4 | 8.94 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 6 | 6x19 | 17.6 | 13.0 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 8 | 6x19 | 31.3 | 23.0 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 10 | 6x19 | 48.5 | 36.0 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 12 | 6x19 | 69.5 | 52.0 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 16 | 6x37 | 119 | 89.0 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 20 | 6x37 | 185 | 138.0 | Galvanized steel | GB/T 20118 / ISO 2408 |
| 24 | 6x37 | 265 | 196.0 | Galvanized steel | GB/T 20118 / ISO 2408 |