Property Class 12.9 Steel Castle Nuts (DIN 935) are supplied to DIN 935. The grade provides requires plating or black-oxide protection and is magnetic; the practical service range is commonly limited to approx. +300 °C; confirm against the coating and the load. Property data, grade comparison and the full size table follow.
Why Choose Property Class 12.9 Steel for Castle Nuts (DIN 935)
The highest common strength class, for high-load machine assembly. For castle nuts (din 935), this matters when requires plating or black-oxide protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 898-1 property class 12.9 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | commonly limited to approx. +300 °C; confirm against the coating and the load |
| Corrosion characteristic | Requires plating or black-oxide protection |
Corrosion Behavior in Service
Carbon and alloy steel castle nuts (din 935) 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
For castle nuts (din 935) 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.
Sizes of Castle Nuts (DIN 935) Available in Property Class 12.9 Steel
| Thread size | Pitch (mm) | Width across flats s (mm) | Total height m (mm) | Slot width n (mm) | Slot depth (mm) | Split pin size | Reference standard |
|---|---|---|---|---|---|---|---|
| M8 | 1.25 | 13.0 | 9.5 | 2.5 | 3.5 | 2 x 25 | DIN 935 |
| M10 | 1.5 | 17.0 | 11.5 | 2.8 | 4.0 | 2.5 x 30 | DIN 935 |
| M12 | 1.75 | 19.0 | 14.0 | 3.5 | 5.5 | 3.2 x 36 | DIN 935 |
| M16 | 2.0 | 24.0 | 17.0 | 4.5 | 6.0 | 4 x 40 | DIN 935 |
| M20 | 2.5 | 30.0 | 20.0 | 4.5 | 6.0 | 4 x 50 | DIN 935 |
| M24 | 3.0 | 36.0 | 24.0 | 5.5 | 8.0 | 5 x 63 | DIN 935 |
Dimensions are independent of the material: every size above is available in Property Class 12.9 Steel.
Custom manufacturing · Made to drawing
Need this nut in a grade that is not listed?
Grade 12 9 Steel is one of the grades the catalog describes. Thread size is the obvious variable and rarely the interesting one — height for clearance, across-flats for the tool already in the cell, and the locking feature for the vibration actually present. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
