Property Class 12.9 Steel Fine-Thread All-Metal Hex Flange Lock Nuts are supplied to ISO 12126. 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 Fine-Thread All-Metal Hex Flange Lock Nuts
The highest common strength class, for high-load machine assembly. For fine-thread all-metal hex flange lock nuts, 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 fine-thread all-metal hex flange lock nuts 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 fine-thread all-metal hex flange lock 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.
Sizes of Fine-Thread All-Metal Hex Flange Lock Nuts Available in Property Class 12.9 Steel
| Size | Pitch P (mm) | c (mm) | d_a_max (mm) | d_a_min (mm) | d_c_max (mm) | d_w_min (mm) | Width across corners e (mm) | h_max (mm) | h_min (mm) | m_min (mm) | m_w_min (mm) | Width across flats s (mm) | s_min (mm) | r_max (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M8x1 | 1 | 1.2 | 8.75 | 8 | 17.9 | 15.8 | 14.38 | 9.4 | 8.74 | 7.64 | 4.6 | 13 | 12.73 | 0.5 | ISO 12126 |
| M10x1 | 1 | 1.5 | 10.8 | 10 | 21.8 | 19.6 | 16.64 | 11.4 | 10.34 | 9.64 | 5.6 | 15 | 14.73 | 0.6 | ISO 12126 |
| (M10x1.25) | 1.25 | 1.5 | 10.8 | 10 | 21.8 | 19.6 | 16.64 | 11.4 | 10.34 | 9.64 | 5.6 | 15 | 14.73 | 0.6 | ISO 12126 |
| M12x1.5 | 1.5 | 1.8 | 13 | 12 | 26 | 23.8 | 20.03 | 13.8 | 12.57 | 11.57 | 6.8 | 18 | 17.73 | 0.7 | ISO 12126 |
| (M12x1.25) | 1.25 | 1.8 | 13 | 12 | 26 | 23.8 | 20.03 | 13.8 | 12.57 | 11.57 | 6.8 | 18 | 17.73 | 0.7 | ISO 12126 |
| (M14x1.5) | 1.5 | 2.1 | 15.1 | 14 | 29.9 | 27.6 | 23.36 | 15.9 | 14.8 | 13.3 | 7.7 | 21 | 20.67 | 0.9 | ISO 12126 |
| M16x1.5 | 1.5 | 2.4 | 17.3 | 16 | 34.5 | 31.9 | 26 | 18.3 | 17.2 | 15.3 | 8.9 | 24 | 23.67 | 1 | ISO 12126 |
| M20x1.5 | 1.5 | 3 | 21.6 | 20 | 42.8 | 39.9 | 32.95 | 22.4 | 20.3 | 18.7 | 10.7 | 30 | 29.16 | 1.2 | ISO 12126 |
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.
