EngiRef / Metric Bolt Specification
M12
M12 coarse-thread metric bolt: 1.75 mm pitch, 12 mm major diameter. Tensile stress area 84.3 mm² per ISO 898-1. Takes a 19 mm wrench. Free bolt specification…
Specification
- Size
- M12
- Pitch (mm)
- 1.75
- Major diameter d (mm)
- 12
- Minor diameter d₃ (mm, external thread)
- 9.85
- Tensile stress area (mm²)
- 84.3
- Head height (mm)
- 7.5
- Head diameter (mm)
- 18
- Wrench size (mm)
- 19
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.