Material specification page for low and high cap (acorn) nuts, inch 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 SAE J483.
Why Choose Property Class 12.9 Steel for Low and High Cap (Acorn) Nuts, Inch
The highest common strength class, for high-load machine assembly. For low and high cap (acorn) nuts, inch, 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 low and high cap (acorn) nuts, inch 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 Low and High Cap (Acorn) Nuts, Inch, 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 Low and High Cap (Acorn) Nuts, Inch Available in Property Class 12.9 Steel
| Size | Type | Threads per inch | Width across flats s (in) | A (in) | Nut height m (in) | Q (in) | U (in) | Reference standard |
|---|---|---|---|---|---|---|---|---|
| #6 | Low cap nuts | 32 | 0.312 | 0.3 | 0.34 | 0.16 | 0.16 | SAE J483 |
| #8 | Low cap nuts | 32 | 0.312 | 0.3 | 0.34 | 0.16 | 0.16 | SAE J483 |
| #10 | Low cap nuts | 24 | 0.375 | 0.36 | 0.41 | 0.19 | 0.19 | SAE J483 |
| #12 | Low cap nuts | 24 | 0.375 | 0.36 | 0.41 | 0.19 | 0.22 | SAE J483 |
| 1/4" | Low cap nuts | 20 | 0.438 | 0.41 | 0.47 | 0.22 | 0.25 | SAE J483 |
| 5/16" | Low cap nuts | 18 | 0.5 | 0.47 | 0.53 | 0.25 | 0.31 | SAE J483 |
| 3/8" | Low cap nuts | 16 | 0.562 | 0.53 | 0.62 | 0.28 | 0.38 | SAE J483 |
| 7/16" | Low cap nuts | 14 | 0.625 | 0.59 | 0.69 | 0.31 | 0.44 | SAE J483 |
| 1/2" | Low cap nuts | 13 | 0.75 | 0.72 | 0.81 | 0.38 | 0.5 | SAE J483 |
| 9/16" | Low cap nuts | 12 | 0.875 | 0.84 | 0.94 | 0.44 | 0.56 | SAE J483 |
| 5/8" | Low cap nuts | 11 | 0.938 | 0.91 | 1 | 0.47 | 0.62 | SAE J483 |
| 3/4" | Low cap nuts | 10 | 1.062 | 1.03 | 1.16 | 0.53 | 0.75 | SAE J483 |
| 7/8" | Low cap nuts | 9 | 1.25 | 1.22 | 1.36 | 0.62 | 0.88 | SAE J483 |
| 1" | Low cap nuts | 8 | 1.438 | 1.41 | 1.55 | 0.72 | 1 | SAE J483 |
| 1 1/8" | Low cap nuts | 7 | 1.625 | 1.59 | 1.75 | 0.81 | 1.12 | SAE J483 |
| 1 1/4" | Low cap nuts | 7 | 1.812 | 1.78 | 1.95 | 0.91 | 1.25 | SAE J483 |
| #6 | High cap nuts | 32 | 0.312 | 0.3 | 0.42 | 0.17 | 0.19 | SAE J483 |
| #8 | High cap nuts | 32 | 0.312 | 0.3 | 0.42 | 0.17 | 0.19 | SAE J483 |
| #10 | High cap nuts | 24 | 0.375 | 0.36 | 0.52 | 0.2 | 0.25 | SAE J483 |
| #12 | High cap nuts | 24 | 0.375 | 0.36 | 0.52 | 0.2 | 0.28 | SAE J483 |
| 1/4" | High cap nuts | 20 | 0.438 | 0.41 | 0.59 | 0.23 | 0.31 | SAE J483 |
| 5/16" | High cap nuts | 18 | 0.5 | 0.47 | 0.69 | 0.28 | 0.38 | SAE J483 |
| 3/8" | High cap nuts | 16 | 0.562 | 0.53 | 0.78 | 0.31 | 0.47 | SAE J483 |
| 7/16" | High cap nuts | 14 | 0.625 | 0.59 | 0.88 | 0.34 | 0.53 | SAE J483 |
| 1/2" | High cap nuts | 13 | 0.75 | 0.72 | 1.03 | 0.42 | 0.62 | SAE J483 |
| 9/16" | High cap nuts | 12 | 0.875 | 0.84 | 1.19 | 0.48 | 0.69 | SAE J483 |
| 5/8" | High cap nuts | 11 | 0.938 | 0.91 | 1.28 | 0.53 | 0.78 | SAE J483 |
| 3/4" | High cap nuts | 10 | 1.062 | 1.03 | 1.45 | 0.59 | 0.94 | SAE J483 |
| 7/8" | High cap nuts | 9 | 1.25 | 1.22 | 1.72 | 0.7 | 1.09 | SAE J483 |
| 1" | High cap nuts | 8 | 1.438 | 1.41 | 1.97 | 0.81 | 1.25 | SAE J483 |
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.
