Product Specifications
| Model / Specification | M3-M10 |
| Material | Carbon steel, Stainless steel |
| Thread size d |
M3 | M4 | M5 | M6 | M8 | M10 | ||
|---|---|---|---|---|---|---|---|---|
| P | Pitch | 0.5 | 0.7 | 0.8 | 1 | 1.25 | 1.5 | |
| dk | Theoretical | Max. | 7.4 | 10.02 | 12 | 14.44 | 19.38 | 23 |
| Actual | Max. | 6.57 | 9.02 | 10.9 | 13.2 | 17.9 | 21.3 | |
| Min. | 6.17 | 8.52 | 10.27 | 12.46 | 17.09 | 20.49 | ||
| ds | Max. | 3 | 4 | 5 | 6 | 8 | 10 | |
| Min. | 2.86 | 3.82 | 4.82 | 5.82 | 7.78 | 9.78 | ||
| k | Max. | 2.2 | 3.01 | 3.5 | 4.22 | 5.69 | 6.5 | |
| Socket | 10 | 20 | 25 | 30 | 45 | 50 | ||
| A | Ref. | 2.8 | 3.95 | 4.5 | 5.6 | 7.93 | 8.95 | |
| t | Max. | 1.18 | 1.69 | 1.89 | 2.22 | 2.99 | 3.3 | |
| Min. | 0.92 | 1.3 | 1.5 | 1.83 | 2.6 | 2.91 | ||
| r | Min. | 0.10 | 0.20 | 0.20 | 0.25 | 0.40 | 0.40 | |
| Thread length b | - | - | - | - | - | - | ||
Dimensions in mm. Data compiled from GB/T 2673.2-2020 for selection reference only; actual supply is subject to drawings and inspection reports.
Product Overview
The hexalobular socket raised countersunk head screw, also known as a Torx raised countersunk screw, is manufactured to GB/T 2673.2-2020. Its raised (enlarged conical) head has a larger cone diameter and greater head height than an ordinary countersunk head, so it sits slightly above the workpiece surface after tightening. This keeps the locating function of the countersink while increasing the bearing area and tensile strength of the head. The drive is a hexalobular (six-lobe / Torx) socket with rounded load flanks that spread the tightening torque evenly, reduce cam-out and suit automated assembly lines.
1. Product Features
- Raised countersunk (enlarged conical) head with a larger cone diameter and greater height than an ordinary countersunk head, giving a bigger bearing area and higher tensile strength.
- Sits slightly above the workpiece surface after assembly, ideal for shallow countersinks or where extra head strength is required.
- Hexalobular (Torx) socket drive: six rounded lobes transmit torque evenly, resist cam-out and protect the recess.
- Thread sizes from M3 to M10, covering a wide range of applications.
- Available in carbon steel and stainless steel, selected according to environment and strength requirements.
2. Product Advantages
- Compared with an ordinary countersunk head, the raised head offers greater load-carrying capacity at the same thread size, making it suitable for joints that must withstand higher tensile loads.
- The hexalobular recess together with a dedicated Torx driver allows higher tightening torque and reduces stripping and rejects during assembly.
- High degree of standardisation: the GB/T 2673.2 dimensional system is complete, which simplifies export matching and second sourcing.
- Material and surface finish can be customised to balance strength, corrosion resistance and cost.
3. Application Scope
- Automotive and rail transit applications that demand high countersunk-head strength and locating accuracy.
- Assembly of structural parts in electronics, instruments and office equipment.
- Stainless steel versions suit damp or mildly corrosive environments, as well as food and medical equipment.
- Automated assembly lines and robotic tightening stations that require high recess fit accuracy.
