EngiRef / Metric Bolt Specification
M30
M30 coarse-thread metric bolt: 3.5 mm pitch, 30 mm major diameter. Tensile stress area 561 mm² per ISO 898-1. Takes a 46 mm wrench. Free bolt specification…
Specification
- Size
- M30
- Pitch (mm)
- 3.5
- Major diameter d (mm)
- 30
- Minor diameter d₃ (mm, external thread)
- 25.71
- Tensile stress area (mm²)
- 561
- Head height (mm)
- 18.7
- Head diameter (mm)
- 46
- Wrench size (mm)
- 46
Tensile stress area follows ISO 898-1, At = (π/4)(d − 0.9382p)². Verify against the current standard and the fastener manufacturer's data before safety-critical design.