Zinc Plated DIN251 8.8 Hexagon Socket Flange Head Allen Bolt
Zinc Plated DIN251 8.8 Hexagon Socket Flange Head Machine Bolt
Standard: DIN251
DIN 251 hexagon socket flange head machine screws are German DIN standard specialized fasteners engineered for industrial mechanical fastening, renowned for their integrated anti-loosening structure, high connection stability and standardized dimensional design. As a mainstream choice for medium and high-load fastening scenarios, this type of machine screw features a one-piece hexagon socket drive and flange head structure, eliminating the need for additional washers in assembly. Paired with the industry-common 8.8 grade mechanical performance and zinc-plated anti-corrosion treatment, DIN 251 screws are widely adopted in various industrial assembly fields with strict requirements for connection firmness and installation efficiency.
- Integrated structure saves assembly time: The flange head replaces the traditional flat washer and spring washer combination, reducing the number of assembly parts and improving fastening efficiency
- Strong anti-loosening performance: The flange surface is designed with anti-slip serrations (optional for standard models), which can effectively prevent the screw from loosening due to mechanical vibration, ensuring long-term connection stability
- Wide compatibility: Standardized DIN 251 dimensions cover mainstream metric thread specifications (M3-M24), adapting to the fastening needs of different industrial workpieces and equipment
- Easy operation: The hexagon socket drive is compatible with universal standard hexagon socket wrenches, with no special tool requirements, and is suitable for narrow and confined installation spaces
DIN 251 8.8 grade zinc-plated hexagon socket flange head machine screws are a versatile industrial fastener, widely used in automobile manufacturing, construction machinery, machine tool equipment, sheet metal cabinet production, electrical and electronic equipment, hydraulic and pneumatic components, and automation equipment assembly. Typical application scenarios include engine component fastening, gearbox assembly, sheet metal cabinet connection, hydraulic cylinder fixed installation, electrical panel mounting, and engineering machinery structural part fastening. It is the preferred fastener for mechanical fastening scenarios that require high connection stability, anti-loosening performance and assembly efficiency, and is favored by industrial manufacturers for its standardized design and reliable performance.
| d | M3 | M4 | M5 | M6 | M8 | M10 |
|---|---|---|---|---|---|---|
| P | 0.5 | 0.7 | 0.8 | 1 | 1.25 | 1.5 |
| dk min | 5.2 | 6.78 | 7.72 | 9.7 | 12.7 | 15.7 |
| dk max | 5.5 | 7 | 8 | 10 | 13 | 16 |
| k min | 2.75 | 3.82 | 4.82 | 5.7 | 7.7 | 9.7 |
| k max | 3 | 4 | 5 | 6 | 8 | 10 |
| dc min | 6.7 | 8.8 | 10.7 | 12.3 | 15.7 | 19.7 |
| dc max | 7 | 9 | 11 | 12.6 | 16 | 20 |
| c min | 0.8 | 1 | 1 | 1.3 | 1.8 | 2 |
| c max | 1 | 1.2 | 1.2 | 1.5 | 2 | 2.2 |
| s | 2.5 | 3 | 4 | 5 | 6 | 8 |
| t min | 1.3 | 2 | 2.5 | 3 | 4 | 5 |
| Teeth | 18 | 18 | 20 | 24 | 24 | 30 |
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