On the bench specifying M8 Phillips Pan Head Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 032)? This page gives the controlling dimensions for the M8 size of Phillips Pan Head Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 032) (to GB/T 845 / ISO 7049).
M8 Dimensional Row (GB/T 845 / ISO 7049)
| Size | Pitch (mm) | Length L (mm) | Head diameter dk (mm) | Head height k (mm) | Cross recess | Reference standard |
|---|---|---|---|---|---|---|
| M8 | 1.25 | 50 | 16.0 | 4.8 | PH3 | ISO 7045 / GB/T 818 |
Spanner & Drive for M8 Phillips Pan Head Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 032)
M8 Phillips Pan Head Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 032) use a PH3 cross recess. Match the driver bit to the recess (Phillips PH / Pozi PZ are NOT interchangeable).
Hole Sizes for M8
| Coarse-thread pitch (ISO 724) | 1.25 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 9 mm |
| Tapping drill, coarse thread | 6.8 mm |
Tightening Torque for M8
| Class 8.8 (dry, ~µ 0.125) | ≈ 25 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 35 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 41 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Common Applications for M8 Phillips Pan Head Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 032)
M8 Phillips Pan Head Self-Tapping Screw — GB/T 845 / ISO 7049 (Series 032) are commonly specified for machine assembly, general engineering, plant maintenance and OEM equipment.
Mating Parts for M8
For M8, pair with a M8 hex nut (ISO 4032 / DIN 934) and, where used, a M8 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
When to Step Up or Down from M8
When the joint preload approaches the proof load of M8 class 8.8, step up to M10 class 8.8 (or move to M8 class 10.9). When the joint is over-specified, M6 often saves weight and cost without losing the safety margin.