Cross recessed hexagonal self tapping screws
GB/T 9456-1988
| Surface | |
|---|---|
| Groove | Cross recess |
| head shape | Hexagon (double chamfer) |
| Thread | Fully threaded |
| Material | |
| standard | GB national standard |
| Grade |
| (mm) | ST2.9 | ST3.5 | ST4.2 | ST4.8 | ST6.3 | ST8 |
|---|---|---|---|---|---|---|
| P | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 2.1 |
| a(max) | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 2.1 |
| da(max) | 3.5 | 4.1 | 4.9 | 5.5 | 7.1 | 9.2 |
| s(max) | 5 | 5.5 | 7 | 8 | 10 | 13 |
| s(min) | 4.82 | 5.32 | 6.78 | 7.78 | 9.78 | 12.73 |
| e(min) | 5.4 | 5.96 | 7.59 | 8.71 | 10.95 | 14.26 |
| k(max) | 2.3 | 2.6 | 3 | 3.8 | 4.7 | 6 |
| k(min) | 2 | 2.3 | 2.6 | 3.3 | 4.1 | 5.2 |
| r(min) | 0.1 | 0.1 | 0.2 | 0.2 | 0.25 | 0.4 |
| No. | 1 | 2 | 2 | 2 | 3 | 3 |
| M | 2.5 | 3.5 | 4 | 4.4 | 6.2 | 7.2 |
| t(min) | 0.95 | 0.91 | 1.4 | 1.8 | 2.36 | 3.2 |
| t(max) | 1.32 | 1.43 | 1.9 | 2.33 | 2.86 | 3.86 |
| d(max) | 2.9 | 3.53 | 4.22 | 4.8 | 6.25 | 8 |
| d(min) | 2.76 | 3.35 | 4.04 | 4.62 | 6.03 | 7.78 |
| d1(max) | 2.18 | 2.64 | 3.1 | 3.58 | 4.88 | 6.2 |
| d1(min) | 2.08 | 2.51 | 2.95 | 3.43 | 4.7 | 5.99 |
| Thread | GB/T 5280 | |
| Mechanical properties | GB/T 3098.5 | |
| tolerance | Product grade | Except for the provisions in Chapter 3, the rest are classified as Class A |
| standard | GB/T 3103.1 | |
| Cross recess | H type GB/T 944.1 | |
| surface treatment | Galvanized passivation GB/T 5267 | |
| Acceptance and packaging | GB/T 90 | |
