Property Class 8.8 Steel Screw-Mount Nuts are supplied to ISO 898-1 property class 8.8. Corrosion behaviour is requires plating (zinc) for corrosion protection, the material is magnetic, and the usable service range is commonly limited to approx. +300 °C; confirm against the coating and the load. In practice this grade is the workhorse medium-carbon alloy class for structural joints.
- Grade
- ISO 898-1 property class 8.8
- Corrosion resistance
- Requires plating (zinc) for corrosion protection
- Magnetic response
- Magnetic
- Service temperature
- commonly limited to approx. +300 °C; confirm against the coating and the load
Property values are typical for the grade. Certified mechanical test data is available on request for production orders.
Material page for screw-mount nuts in Property Class 8.8 Steel (ISO 898-1 property class 8.8). The sizes below are the ones we supply; there is no published dimensional standard for this article, so the table rather than a standard number is what to quote. Corrosion behaviour is requires plating (zinc) for corrosion protection and the service range is commonly limited to approx. +300 °C; confirm against the coating and the load.
Why Choose Property Class 8.8 Steel for Screw-Mount Nuts
The workhorse medium-carbon alloy class for structural joints. For screw-mount nuts, this matters when requires plating (zinc) for corrosion protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 898-1 property class 8.8 |
|---|
| Magnetic response | Magnetic |
|---|
| Service temperature | commonly limited to approx. +300 °C; confirm against the coating and the load |
|---|
| Corrosion characteristic | Requires plating (zinc) for corrosion protection |
|---|
Corrosion Behavior in Service
Carbon and alloy steel screw-mount 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.
Comparable Grades
For Screw-Mount Nuts, class 10.9 or 12.9 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 Screw-Mount Nuts Available in Property Class 8.8 Steel
| Thread size | Base diameter (in) | Base thickness (in) | Barrel diameter (in) | Barrel height (in) | Mounting-hole diameter (in) | Mounting holes |
|---|
| 6-32 | 9/16 | 1/32 | 11/64 | 1/4 | 5/64 | 3 |
| 8-32 | 23/32 | | 7/32 | | | 3 |
| 10-24 | 3/4 | | 1/4 | 9/32 | 7/64 | 3 |
Dimensions are independent of the material: every size above is available in Property Class 8.8 Steel.
Custom manufacturing · Made to drawing
Need this nut in a grade that is not listed?
Grade 8 8 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.
Custom nut manufacturingSend a drawing
Applications & Industries
Screw-Mount Nuts are bought for a small number of well-defined jobs. These are the ones we ship them for. Stocked from 6-32 to 10-24 (nominal diameter).
Industries that specify Screw-Mount Nuts
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Repair work
A replacement nut can be installed without changing the panel thread.
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Appliance panels
Three-hole mounting nuts add a threaded barrel to a thin sheet.
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Electrical housings
Screws, rivets or nails hold the base when a rear nut is not practical.
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Light fabrication
Base and barrel dimensions fit small brackets and covers.
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Building services
Threaded rod, channel and suspension assemblies.
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Machine building & OEM
The clamping counter-face on studs and bolts throughout an assembly.
Typical applications
- using screws, rivets or nails in the base holes
- mounting a threaded barrel through three small fixing holes
- matching base diameter and barrel height to the panel
- selecting the 6-32, 8-32 or 10-24 thread
- joints re-torqued at a service interval
- completing a bolted joint on a stud, rod or bolt
Service conditions to specify against
- Marine and coastal
- Available in A4 (316) stainless for chloride exposure — coastal structures, pool halls, water treatment and deck hardware, where A2 will eventually pit.
- High load
- Supplied in ISO 898-1 property classes, so the joint can be designed to a stated proof load and tightened to a calculated torque rather than by feel.
- Match the class
- A nut below the bolt property class strips before the bolt reaches its own limit — pair class 8 nuts with 8.8 bolts, class 10 with 10.9.
Where to use something else
- Do not assume the mounting holes carry the same load as a through-bolted flange; the thin base and parent sheet govern retention.
Full application guide: where Screw-Mount Nuts are used, how to specify them, and the cases they are wrong for
