Product Description
M12 Grade 8.8 Zinc Plated Serrated Flange Bolts – Part Threaded
M12 Grade 8.8 high tensile steel hexagon flange bolts with a zinc plated finish. These bolts feature serrations beneath the integral flange and a partially threaded body with an unthreaded shank.
The flange provides a broad bearing surface, while the serrations grip the mating surface to help resist loosening. Available in 40mm and 45mm lengths with standard M12 × 1.75mm metric coarse threads.
Specifications
| Product type | Part-threaded hexagon flange bolt |
|---|---|
| Nominal thread diameter | M12 — 12mm |
| Thread pitch | 1.75mm |
| Thread type | Metric coarse, right-hand |
| Thread coverage | Part threaded, with an unthreaded shank |
| Material | High tensile steel |
| Property class | 8.8 |
| Finish | Zinc plated |
| Head style | External hexagon with integral flange |
| Flange underside | Serrated |
| Spanner size | 16mm across flats |
| Guide flange diameter | 26.6mm |
| Guide head height | 11.5mm |
Available Lengths and Thread Coverage
| Bolt Size | Length Beneath Flange (mm) | Guide Thread Length (mm) | Guide Plain Length (mm) |
|---|---|---|---|
| M12 × 40mm | 40 | 30 | 10 |
| M12 × 45mm | 45 | 30 | 15 |
Bolt length is measured from beneath the flange to the tip. Thread and plain lengths are guide dimensions; check the actual bolt where the thread runout position is critical.
Key Features
- Grade 8.8 high tensile steel construction.
- Serrated flange underside helps resist loosening.
- Integral flange distributes the clamping load.
- Part-threaded body with an unthreaded shank.
- Zinc plated finish provides corrosion protection.
- 16mm external hexagon drive.
Typical Applications
Machinery, brackets, frames and general engineering assemblies requiring M12 part-threaded bolts with serrated flange heads.
Installation
Match the M12 × 1.75mm thread to the mating component. Select a length that provides sufficient thread engagement and allows the joint to clamp fully without binding on the unthreaded shank. Tighten with a correctly fitting 16mm spanner or socket to the torque specified for the assembly.
The serrations contact the mating surface directly and may mark painted, plated or softer surfaces. Check that this bearing arrangement suits the joint.
Ordering
Select 40mm or 45mm length. Pack quantities available: 1, 5, 10, 20, 50, 100, 250, 500 or 1000 bolts.
Standards
- DIN 6921 — hexagon flange head dimensional pattern, with serrated underside.
- ISO 898-1 — mechanical property classification for Class 8.8 steel fasteners.
