M6 Phillips Pan Head Machine Screw (GB/T 818 / ISO 7045) are specified by thread size, length and head dimensions. The M6 row from the standard is reproduced below, followed by the drill sizes, spanner size and torque values used when installing this size.
M6 Dimensional Row (GB/T 818 / ISO 7045)
| Size | Pitch (mm) | Length L (mm) | Head diameter dk (mm) | Head height k (mm) | Cross recess | Reference standard |
|---|---|---|---|---|---|---|
| M6 | 1.0 | 40 | 12.0 | 3.6 | PH3 | ISO 7045 / GB/T 818 |
Spanner & Drive for M6 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 033)
M6 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 033) use a PH3 cross recess. Match the driver bit to the recess (Phillips PH / Pozi PZ are NOT interchangeable).
Hole Sizes for M6
| Coarse-thread pitch (ISO 724) | 1 mm |
|---|---|
| Through-hole / clearance (ISO 273 medium) | 6.6 mm |
| Tapping drill, coarse thread | 5 mm |
Tightening Torque for M6
| Class 8.8 (dry, ~µ 0.125) | ≈ 10 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 14 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 17 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.
Proof Load & Strength for M6
| Tensile stress area As (ISO 898-1) | 20.1 mm² |
|---|---|
| Proof load, class 8.8 | 12 kN |
| Proof load, class 10.9 | 17 kN |
| Proof load, class 12.9 | 19 kN |
| Min. ultimate tensile, class 8.8 | 16 kN |
Proof load = stress area × proof stress per ISO 898-1. Design joints so the working preload stays below the proof load of the selected class.
M6 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 033) Weight
A steel M6 phillips pan head machine screw at the listed 40 mm length weighs approximately 36 g each — about 36 kg per 1,000 pieces. Stainless A2/A4 weighs roughly the same (density 7.9–8.0 g/cm³). Actual weight varies slightly with head form, thread and finish; use this figure for freight estimation only.
Common Applications for M6 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 033)
M6 Phillips Pan Head Machine Screw — GB/T 818 / ISO 7045 (Series 033) are commonly specified for machine assembly, general engineering, plant maintenance and OEM equipment.
Mating Parts for M6
For M6, pair with a M6 hex nut (ISO 4032 / DIN 934) and, where used, a M6 flat washer (ISO 7089 / DIN 125A) under the head and under the nut.
When to Step Up or Down from M6
When the joint preload approaches the proof load of M6 class 8.8, step up to M8 class 8.8 (or move to M6 class 10.9). When the joint is over-specified, M5 often saves weight and cost without losing the safety margin.