Property Class 8.8 Steel Closed-End Round-Body Blind Rivet 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.
Property Class 8.8 Steel (ISO 898-1 property class 8.8) is the workhorse medium-carbon alloy class for structural joints. When closed-end round-body blind rivet nuts are specified in this grade, the dimensions remain per Trade series (closed-end blind rivet nuts); the material determines corrosion behavior (requires plating (zinc) for corrosion protection) and the service temperature range (commonly limited to approx. +300 °C; confirm against the coating and the load). Both are covered below with the size table.
Why Choose Property Class 8.8 Steel for Closed-End Round-Body Blind Rivet Nuts
The workhorse medium-carbon alloy class for structural joints. For closed-end round-body blind rivet 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 |
|---|
Galvanic & Galling Considerations
For closed-end round-body blind rivet 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.
Comparable Grades
For Closed-End Round-Body Blind Rivet 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 Closed-End Round-Body Blind Rivet Nuts Available in Property Class 8.8 Steel
| Thread size | Pitch (mm) | Grip range (mm) | Installation hole (mm) | Head diameter (mm) | End | Material options |
|---|
| M4 | 0.7 | 0.5~2.5 | 6.1 | 9.0 | closed | zinc-plated steel / stainless steel / aluminum alloy |
| M5 | 0.8 | 0.5~3.0 | 7.1 | 10.0 | closed | zinc-plated steel / stainless steel / aluminum alloy |
| M6 | 1.0 | 0.5~3.0 / 3.0~5.0 | 9.1 | 12.0 | closed | zinc-plated steel / stainless steel / aluminum alloy |
| M8 | 1.25 | 0.5~3.0 / 3.0~5.5 | 11.1 | 15.0 | closed | zinc-plated steel / stainless steel / aluminum alloy |
| M10 | 1.5 | 1.0~3.5 | 13.1 | 17.0 | closed | zinc-plated steel / stainless steel / aluminum alloy |
Applications & Industries
What Closed-End Round-Body Blind Rivet Nuts are specified for, industry by industry. Stocked from M4 to M10.
Industries that specify Closed-End Round-Body Blind Rivet Nuts
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Outdoor enclosures
Cover and bracket attachment points exposed to water and dirt.
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HVAC fabrication
Panel hardware installed after the duct or enclosure has been formed.
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Refrigeration equipment
Sealed threaded mounting points in formed panels and closed housings.
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Vehicle bodywork
Blind threads in rails and box sections where the cavity must stay closed.
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Automotive & transport
Vibration-prone joints where the locking type is specified on the drawing.
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Maintenance & MRO
Replacements matched to the existing bolt class, thread and finish.
Typical applications
- forming the blind bulb within the specified grip range
- choosing steel, stainless steel or aluminum for the service environment
- adding a sealed internal thread from the front face of a panel
- keeping water and debris out of a closed section behind the insert
- 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 drill to the thread minor diameter; the installation hole is set by the body and forming requirements.
Full application guide: where Closed-End Round-Body Blind Rivet Nuts are used, how to specify them, and the cases they are wrong for
