Grade 12.9 Steel Lifting Eye Nuts combine the dimensional form of DIN 582 with the material properties of grade class 12.9: requires plating or black-oxide protection, magnetic, service range up to approx. +300 °C. This page summarizes the grade data, its corrosion behavior in service, the comparable grades, and the sizes supplied.
Why Choose Grade 12.9 Steel for Lifting Eye Nuts
The highest common strength class, for high-load machine assembly. For lifting eye nuts, 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 |
Galvanic & Galling Considerations
For lifting eye nuts in steel, the dominant compatibility issue is hydrogen embrittlement at high property classes (10.9 and above) when electroplated. Plating must be followed by an appropriate baking treatment, or a non-electroplated finish (mechanical zinc, zinc flake) should be substituted.
Comparable Grades
For Lifting Eye Nuts, 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 Lifting Eye Nuts Available in Grade 12.9 Steel
| Thread size | Pitch (mm) | Ring inside diameter d (mm) | Ring outside diameter (mm) | Total height (mm) | Max load vertical (kg) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| M6 | 1.0 | 20 | 36 | 36 | 70 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M8 | 1.25 | 25 | 45 | 45 | 140 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M10 | 1.5 | 30 | 54 | 54 | 230 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M12 | 1.75 | 36 | 63 | 63 | 340 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M16 | 2.0 | 45 | 81 | 81 | 700 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M20 | 2.5 | 56 | 99 | 99 | 1200 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M24 | 3.0 | 63 | 117 | 117 | 1800 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M30 | 3.5 | 80 | 144 | 144 | 3200 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |
| M36 | 4.0 | 95 | 171 | 171 | 4600 | DIN 582 / WLL | Drop-forged lifting eye nut, vertical pull |