Property Class 12.9 Steel Server Rack Screws and Cage-Nut Hardware are supplied to ISO 898-1 property class 12.9. Corrosion behaviour is requires plating or black-oxide 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 highest common strength class, for high-load machine assembly.
- Grade
- ISO 898-1 property class 12.9
- Corrosion resistance
- Requires plating or black-oxide 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 12.9 Steel Server Rack Screws and Cage-Nut Hardware are supplied to our own published dimensions — this is a trade-series article rather than one covered by a dimensional standard, so confirm the figures against the part you are replacing. The grade provides requires plating or black-oxide protection and is magnetic; the practical service range is commonly limited to approx. +300 °C; confirm against the coating and the load.
Why Choose Property Class 12.9 Steel for Server Rack Screws and Cage-Nut Hardware
The highest common strength class, for high-load machine assembly. For server rack screws and cage-nut hardware, 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 server rack screws and cage-nut hardware 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 Server Rack Screws and Cage-Nut Hardware, 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 Server Rack Screws and Cage-Nut Hardware Available in Property Class 12.9 Steel
| Thread family | Representative screw lengths | Nominal diameter / pitch | Head form | Mating hardware |
|---|
| 10-32 | 3/8 / 1/2 / 5/8 in | about 3/16 in; 32 TPI | pan head | cage nut or threaded rack hole |
| 12-24 | 3/8 / 1/2 / 5/8 in | about 7/32 in; 24 TPI | pan head | cage nut or threaded rack hole |
| M6 | 10 / 16 mm | 6 mm; 1.0 pitch | pan head | cage nut or threaded rack hole |
Dimensions are independent of the material: every size above is available in Property Class 12.9 Steel.
Custom manufacturing · Made to drawing
Need this screw in a grade that is not listed?
Grade 12 9 Steel is one of the grades the catalog describes. Lengths and thread lengths outside the standard table are the commonest request, followed by a drive the standard does not offer and a head marked with your own part number. Made by cold heading or warm forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
Custom screw manufacturingSend a drawing
Applications & Industries
The sectors that buy Server Rack Screws and Cage-Nut Hardware, and the duty each one buys them for. Stocked from 10-32 to M6.
Industries that specify Server Rack Screws and Cage-Nut Hardware
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Audio racks
10-32 hardware is common where the rack is threaded for that system.
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IT equipment
M6 and 12-24 options cover different rack conventions.
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Rack service
Pan-head lengths suit front-panel and rail thickness.
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Data centers
Rack screws and cage nuts attach rails and equipment to cabinet posts.
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Automotive & transport
Chassis, driveline and body fixings that see vibration and are assembled to a controlled preload.
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Steel fabrication
Bolted connections in frames, enclosures, walkways and weldments, on the bench and on site.
Typical applications
- selecting 3/8–5/8 in or 10/16 mm length
- using a cage nut in an unthreaded square rack hole
- keeping the screw thread family consistent across the cabinet
- matching 10-32, 12-24 or M6 to the rack system
- bolting brackets, motors and gearboxes to a frame
- assemblies that are dismantled for service and re-torqued
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.
- Torque and preload
- The joint is designed around bolt tension, so lubrication, coating and the friction coefficient all change the torque figure — state them together.
Where to use something else
- Do not substitute 10-32, 12-24 and M6 by apparent diameter; their pitches are different and cross-threading damages the rack.
- Do not use a machine thread into unthreaded sheet or timber; use a tapping screw, rivet nut or insert made for that parent material.
Full application guide: where Server Rack Screws and Cage-Nut Hardware are used, how to specify them, and the cases they are wrong for
