Product Description:
DIN6921 Hexagon Head Flange bolt is a type of hexagon head bolt with a built-in flange. This design combines the easy operation characteristics of hexagon bolts with the anti-slip fastening advantages of flange structures. The bolt can achieve stable connections without the need for additional gaskets.
Features:
Core Structure
The bolt head is a standard hexagonal shape, compatible with tools such as wrenches, making it easy to quickly tighten and disassemble. The lower part of the head is integrally formed with a ring-shaped flange surface, some of which have anti slip serrations to enhance the locking effect. The rod is designed with full or half threads according to the connection requirements to ensure effective engagement with the nut.
Other standards: German DIN 931/933, American ANSI B18.2.1, etc.
Core Strengths
1. Increase the contact area of the flange surface to evenly distribute pressure and reduce damage to the surface of the connecting parts.
2. The serrated flange surface can produce mechanical locking effect, and its anti-vibration and anti-loosening effect far exceeds that of ordinary bolts, making it suitable for dynamic working conditions.
3. The integrated flange design eliminates the step of separately installing gaskets, simplifies the assembly process, and improves construction efficiency.
Technical Parameters:
| Screw Thread | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M20 |
| P | Pitch | Coarse thread | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2 | 2.5 |
| Fine thread-1 | / | / | 1 | 1.25 | 1.5 | 1.5 | 1.5 | 1.5 |
| Fine thread-2 | / | / | / | 1 | 1.25 | / | / | / |
| b | L≤125 | 16 | 18 | 22 | 26 | 30 | 34 | 38 | 46 |
| 125＜L≤200 | / | / | 28 | 32 | 36 | 40 | 44 | 52 |
| L＞200 | / | / | / | / | / | / | 57 | 65 |
| c | min | 1 | 1.1 | 1.2 | 1.5 | 1.8 | 2.1 | 2.4 | 3 |
| da | Form A | max | 5.7 | 6.8 | 9.2 | 11.2 | 13.7 | 15.7 | 17.7 | 22.4 |
| Form B | max | 6.2 | 7.4 | 10 | 12.6 | 15.2 | 17.7 | 20.7 | 25.7 |
| dc | max | 11.8 | 14.2 | 18 | 22.3 | 26.6 | 30.5 | 35 | 43 |
| ds | max | 5 | 6 | 8 | 10 | 12 | 14 | 16 | 20 |
| min | 4.82 | 5.82 | 7.78 | 9.78 | 11.73 | 13.73 | 15.73 | 19.67 |
| du | max | 5.5 | 6.6 | 9 | 11 | 13.5 | 15.5 | 17.5 | 22 |
| dw | min | 9.8 | 12.2 | 15.8 | 19.6 | 23.8 | 27.6 | 31.9 | 39.9 |
| e | min | 8.71 | 10.95 | 14.26 | 16.5 | 17.62 | 19.86 | 23.15 | 29.87 |
| f | max | 1.4 | 2 | 2 | 2 | 3 | 3 | 3 | 4 |
| k | max | 5.4 | 6.6 | 8.1 | 9.2 | 11.5 | 12.8 | 14.4 | 17.1 |
| k1 | min | 2 | 2.5 | 3.2 | 3.6 | 4.6 | 5.1 | 5.8 | 6.8 |
| r1 | min | 0.25 | 0.4 | 0.4 | 0.4 | 0.6 | 0.6 | 0.6 | 0.8 |
| r2 | max | 0.3 | 0.4 | 0.5 | 0.6 | 0.7 | 0.9 | 1 | 1.2 |
| r3 | min | 0.1 | 0.1 | 0.15 | 0.2 | 0.25 | 0.3 | 0.35 | 0.4 |
| r4 | ≈ | 3 | 3.4 | 4.3 | 4.3 | 6.4 | 6.4 | 6.4 | 8.5 |
| s | max=nominal size | 8 | 10 | 13 | 15 | 16 | 18 | 21 | 27 |
| min | 7.78 | 9.78 | 12.73 | 14.73 | 15.73 | 17.73 | 20.67 | 26.67 |
| t | max | 0.15 | 0.2 | 0.25 | 0.3 | 0.35 | 0.45 | 0.5 | 0.65 |
| min | 0.05 | 0.05 | 0.1 | 0.15 | 0.15 | 0.2 | 0.25 | 0.3 |
Applications:
Typical application areas
Widely used in various industries, including automobiles, machinery, construction, home appliances, and pipeline engineering. For instance, it is utilized for securing automotive chassis and engine components, as well as for linking the shell and bracket of mechanical equipment. Additionally, it is employed for sealing and fastening pipeline flanges, as well as for the internal structure assembly of household appliances like washing machines and air conditioners.
