Material specification page for hex thick nuts (din 6330) in Property Class 12.9 Steel. Covers the grade designation (ISO 898-1 property class 12.9), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to DIN 6330.
Why Choose Property Class 12.9 Steel for Hex Thick Nuts (DIN 6330)
The highest common strength class, for high-load machine assembly. For hex thick nuts (din 6330), 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 hex thick nuts (din 6330) 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 Hex Thick Nuts (DIN 6330), 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 Hex Thick Nuts (DIN 6330) Available in Property Class 12.9 Steel
| Thread size | Pitch (mm) | Width across flats s (mm) | Nut height m (mm) | Height ratio m/d | Engaged threads | Property class | Reference standard |
|---|---|---|---|---|---|---|---|
| M8 | 1.25 | 13.0 | 12.0 | 1.5 | approx. 9.6 | 10 | DIN 6330 |
| M10 | 1.5 | 17.0 | 15.0 | 1.5 | approx. 10.0 | 10 | DIN 6330 |
| M12 | 1.75 | 19.0 | 18.0 | 1.5 | approx. 10.3 | 10 | DIN 6330 |
| M16 | 2.0 | 24.0 | 24.0 | 1.5 | approx. 12.0 | 10 | DIN 6330 |
| M20 | 2.5 | 30.0 | 30.0 | 1.5 | approx. 12.0 | 10 | DIN 6330 |
| M24 | 3.0 | 36.0 | 36.0 | 1.5 | approx. 12.0 | 10 | DIN 6330 |
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. Height and across-flats are the two most often changed — a thinner nut for clearance, a larger hex for a tool that is already on the line. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
