Property Class 12.9 Steel Fine-Thread Hex Flange Bolts, Small Series combine the dimensional form of ISO 15072 with the material properties of grade ISO 898-1 property class 12.9: requires plating or black-oxide protection, magnetic, service range commonly limited to approx. +300 °C; confirm against the coating and the load. This page summarizes the grade data, its corrosion behavior in service, the comparable grades, and the sizes supplied.
Why Choose Property Class 12.9 Steel for Fine-Thread Hex Flange Bolts, Small Series
The highest common strength class, for high-load machine assembly. For fine-thread hex flange bolts, small series, 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 |
Galvanic & Galling Considerations
For fine-thread hex flange bolts, small series 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 Fine-Thread Hex Flange Bolts, Small Series, 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 Fine-Thread Hex Flange Bolts, Small Series Available in Property Class 12.9 Steel
| Size | Pitch P (mm) | a_max (mm) | a_min (mm) | b_0 (mm) | b_1 (mm) | b_2 (mm) | b_3 (mm) | c_min (mm) | d_a_max_F (mm) | d_a_max_U (mm) | d_c_max (mm) | d_s_max (mm) | d_s_min (mm) | d_v_max (mm) | d_w_min (mm) | Width across corners e (mm) | Head height k (mm) | k_w_min (mm) | l_f_max (mm) | r_1_min (mm) | r_2_max (mm) | r_3_max (mm) | r_3_min (mm) | r_4_ref (mm) | Width across flats s (mm) | s_min (mm) | v_max (mm) | v_min (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M8x1 | 1 | 3 | 1 | 35 | 22 | 28 | 0 | 1.2 | 9.2 | 10 | 17 | 8 | 7.78 | 8.8 | 14.9 | 10.95 | 8.5 | 3.8 | 2.1 | 0.4 | 0.5 | 0.36 | 0.16 | 5.7 | 10 | 9.78 | 0.25 | 0.1 | 16~80 | ISO 15072 |
| M10x1 | 1 | 3 | 1 | 40 | 26 | 32 | 0 | 1.5 | 11.2 | 12.5 | 20.8 | 10 | 9.78 | 10.8 | 18.7 | 14.26 | 9.7 | 4.3 | 2.1 | 0.4 | 0.6 | 0.45 | 0.2 | 5.7 | 13 | 12.73 | 0.3 | 0.15 | 20~100 | ISO 15072 |
| M10x1.25 | 1.25 | 3 | 1 | 40 | 26 | 32 | 0 | 1.5 | 11.2 | 12.5 | 20.8 | 10 | 9.78 | 10.8 | 18.7 | 14.26 | 9.7 | 4.3 | 2.1 | 0.4 | 0.6 | 0.45 | 0.2 | 5.7 | 13 | 12.73 | 0.3 | 0.15 | 20~100 | ISO 15072 |
| M12x1.25 | 1.25 | 4.5 | 1.5 | 45 | 30 | 36 | 0 | 1.8 | 13.7 | 15.2 | 24.7 | 12 | 11.73 | 12.8 | 22.5 | 16.5 | 12.1 | 5.4 | 2.1 | 0.6 | 0.7 | 0.54 | 0.24 | 5.7 | 15 | 14.73 | 0.35 | 0.15 | 25~120 | ISO 15072 |
| M12x1.5 | 1.5 | 4.5 | 1.5 | 45 | 30 | 36 | 0 | 1.8 | 13.7 | 15.2 | 24.7 | 12 | 11.73 | 12.8 | 22.5 | 16.5 | 12.1 | 5.4 | 2.1 | 0.6 | 0.7 | 0.54 | 0.24 | 5.7 | 15 | 14.73 | 0.35 | 0.15 | 25~120 | ISO 15072 |
| (M14x1.5) | 1.5 | 4.5 | 1.5 | 50 | 34 | 40 | 0 | 2.1 | 15.7 | 17.7 | 28.6 | 14 | 13.73 | 14.8 | 26.4 | 19.86 | 12.9 | 5.6 | 2.1 | 0.6 | 0.9 | 0.63 | 0.28 | 5.7 | 18 | 17.73 | 0.45 | 0.2 | 30~140 | ISO 15072 |
| M16x1.5 | 1.5 | 4.5 | 1.5 | 55 | 38 | 44 | 57 | 2.4 | 17.7 | 20.5 | 32.8 | 16 | 15.73 | 17.2 | 30.6 | 23.15 | 15.2 | 6.8 | 3.2 | 0.6 | 1 | 0.72 | 0.32 | 8.8 | 21 | 20.67 | 0.5 | 0.25 | 35~160 | ISO 15072 |
Dimensions are independent of the material: every size above is available in Property Class 12.9 Steel.
Custom manufacturing · Made to drawing
Need this bolt in a grade that is not listed?
Grade 12 9 Steel is one of the grades the catalog describes. Head form and drive can be specified to the assembly rather than to a standard: a larger bearing face, a security drive, or a socket sized for the tool already on the bench. Made by cold heading or hot forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
