For aerospace two-lug floating self-locking nutplates in Property Class 12.9 Steel, the controlling selection factors are corrosion exposure, strength requirement and service temperature. The grade data for Property Class 12.9 Steel (ISO 898-1 property class 12.9) is summarized below together with every size supplied.
Why Choose Property Class 12.9 Steel for Aerospace Two-Lug Floating Self-Locking Nutplates
The highest common strength class, for high-load machine assembly. For aerospace two-lug floating self-locking nutplates, 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 aerospace two-lug floating self-locking nutplates 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 aerospace two-lug floating self-locking nutplates 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 Aerospace Two-Lug Floating Self-Locking Nutplates Available in Property Class 12.9 Steel
| Thread size | Overall length A (in) | Width B (in) | Mounting-hole spacing J (in) | Nut height (in) | Material options | Reference standard |
|---|---|---|---|---|---|---|
| 4-40 | 0.948 | 0.416 | 0.688 | 0.175 | cadmium-plated alloy steel or stainless steel | MS21059 and NASM25027 |
| 6-32 | 0.948~1.292 | 0.416~0.680 | 0.688~1.000 | 0.175~0.344 | cadmium-plated alloy steel or stainless steel | MS21059 and NASM25027 |
| 8-32 | 0.948~1.292 | 0.416~0.680 | 0.688~1.000 | 0.175~0.344 | cadmium-plated alloy steel or stainless steel | MS21059 and NASM25027 |
| 10-32 | 0.948~1.292 | 0.416~0.680 | 0.688~1.000 | 0.175~0.344 | cadmium-plated alloy steel or stainless steel | MS21059 and NASM25027 |
| 1/4-28 | 0.948~1.292 | 0.416~0.680 | 0.688~1.000 | 0.175~0.344 | cadmium-plated alloy steel or stainless steel | MS21059 and NASM25027 |
| 5/16-24 | 0.948~1.292 | 0.416~0.680 | 0.688~1.000 | 0.175~0.344 | cadmium-plated alloy steel or stainless steel | MS21059 and NASM25027 |
| 3/8-24 | 0.948~1.292 | 0.416~0.680 | 0.688~1.000 | 0.175~0.344 | cadmium-plated alloy steel or stainless steel | MS21059 and NASM25027 |
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. Locking method is specifiable independently of the rest: nylon insert, all-metal deformed thread, serrated flange, or none. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
