Property Class 12.9 Alloy Steel Socket Head Cap Screws
DISLAB Precision supplies property class 12.9 alloy steel socket head cap screws for machinery, industrial equipment, fixtures, and mechanical assemblies. The cylindrical head and internal hex drive provide a practical fastening option where access around the head is limited. Supplier dimensional data covers metric sizes from approximately M1.6 to M20, with multiple lengths to discuss for each diameter.
Send us your required diameter, pitch, length, quantity, and finish for a quotation. If the assembly depends on a particular head dimension, thread configuration, or documentation package, include those requirements with your inquiry so they can be checked before an order is placed.
12.9 Grade Socket Head Cap Screws for Industrial Fastening
These screws combine alloy steel construction with a property class 12.9 designation. They have a cylindrical socket head and an internal hex drive, so a matching hex key or bit engages inside the head. This geometry can be useful in assemblies with limited clearance for an external wrench. It does not eliminate the need to check tool access above the head or the available depth around the fastener.
For buyers, the main selection questions are the nominal thread diameter, pitch, screw length, head clearance, and whether full or partial threading is needed. The correct choice also depends on the mating thread, joint design, installation method, and operating environment. The dimensional table below is a purchasing reference based on supplier measurements; it is not a certification or a substitute for a drawing when a dimension is critical.
Key Features
Specify the required property class on the purchase inquiry and request supporting documentation if your project needs it.
The product family uses alloy steel. The exact alloy specification should be confirmed against the ordered part.
A hex key or bit fits into the socket, which can simplify access where an external wrench has limited room.
Head diameter and height vary with thread size. Check both against the available assembly space.
Supplier dimensional information includes sizes from approximately M1.6 through M20.
Multiple lengths and fully threaded configurations can be reviewed for the required diameter and quantity.
Dimensions and Size Range
The table gives the supplier-measured thread pitch and principal head dimensions for the listed metric diameters. It helps an engineer or purchaser compare a proposed fastener with the mating thread and available head space. Values are supplied for reference during inquiry; confirm the drawing and production availability for the exact diameter and length you need.
| Thread Size | Pitch P (mm) | Head Diameter dk (mm) | Hex Socket S (mm) | Head Height k (mm) |
|---|---|---|---|---|
| M1.6 | 0.35 | 3 | 1.5 | 1.6 |
| M2 | 0.40 | 4 | 1.5 | 2 |
| M2.5 | 0.45 | 4.5 | 2 | 2.5 |
| M3 | 0.50 | 5.5 | 2.5 | 3 |
| M4 | 0.70 | 7 | 3 | 4 |
| M5 | 0.80 | 8.5 | 4 | 5 |
| M6 | 1.00 | 10.22 | 5 | 6 |
| M8 | 1.25 | 13 | 6 | 8 |
| M10 | 1.50 | 16 | 8 | 10 |
| M12 | 1.75 | 18.1 | 10 | 12 |
| M14 | 2.00 | 21.1 | 12 | 14 |
| M16 | 2.00 | 24.1 | 14 | 16 |
| M18 | 2.50 | 27.1 | 14 | 18 |
| M20 | 2.50 | 30.1 | 17 | 20 |
Dimensions above are based on supplier measurement data and may vary slightly by production batch. Please confirm critical dimensions before ordering.
How to Read Socket Head Cap Screw Dimensions
Use the same symbols when sending a drawing or checking a dimensional requirement. Stating all relevant dimensions reduces the chance of quoting a screw that fits the thread but not the available head space.
- d — nominal thread diameter
- P — thread pitch
- dk — head diameter
- S — hex socket size
- k — head height
- L — screw length
Material and Finish Options
The stated material is alloy steel, and the stated property class is 12.9. The available information does not establish an exact alloy chemistry for every size. If a material grade, certificate, inspection report, or other documentation is required, specify it before quotation.
The product is shown with a black appearance. Black surface finishes and other finishing options may be available depending on size, quantity, and application requirements. Please confirm the required finish when requesting a quotation. Appearance alone does not identify a coating or establish corrosion performance.
Available Sizes and Lengths
Supplier dimensional information covers approximately M1.6 to M20. Multiple lengths are shown for this product family, but the available diameter and length combinations depend on the requested configuration and current production availability. No single length range should be assumed to apply to every thread size.
Send the diameter, pitch, length, quantity, desired finish, and any drawing or specification. If the screw must be fully threaded, state that requirement explicitly. A partial thread request can also be reviewed, but availability must be confirmed for the exact size and length.
Product Catalog
Download our product catalog for a concise overview of metric sizes, dimensional references, product features and RFQ information.
Typical Applications
Socket head cap screws are commonly considered where a compact head and internal hex drive suit the assembly layout. The appropriate fastener still depends on joint design, access, mating material, and installation requirements.
- Industrial machinery and production equipment
- Automation equipment and machine frames
- Machine tools and serviceable assemblies
- Fixtures, tooling, and equipment housings
- Mechanical assemblies with limited wrench clearance
- General equipment manufacturing
How to Request a Quote
A useful inquiry gives the supplier enough information to confirm the configuration before pricing. If you have an existing drawing or sample, include it so critical dimensions and installation constraints can be reviewed alongside the size designation.
- Thread diameter and pitch
- Screw length
- Required quantity
- Property class
- Requested surface finish
- Full or partial thread requirement
- Drawing or critical dimensions
- Packaging requirements
- Required documentation, if any
Use the form below to request a quote or send your drawing to the listed contact address. We can review the requested configuration, dimensional requirements, and packaging needs before confirming supply.
Go to the quote formFrequently Asked Questions
What does property class 12.9 mean?
It is a metric fastener property class designation associated with a high-strength steel fastener. For a purchasing or engineering requirement, specify the property class and ask which exact-product documentation can be provided. This page does not state a tested strength value for a particular batch.
What sizes of socket head cap screws are available?
Supplier measurement data lists metric thread sizes from approximately M1.6 to M20. Actual size and length availability should be confirmed for your requested quantity and configuration.
Are these socket head cap screws fully threaded?
Fully threaded configurations are available for many sizes. Thread configuration should be confirmed for the required diameter and length before ordering.
What surface finishes are available?
Black surface finishes and other options may be reviewed according to the order requirements. State the finish you need in the inquiry; coating type and any performance requirement must be confirmed for the exact product.
Can custom sizes or packaging be supplied?
Custom requirements can be reviewed based on drawing, quantity, and production feasibility. Include any packaging or labeling requirement with the quote request.
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