M6 12.9 Dacromet Gumet Hot Dip Galvanized HDG 12 Point Head Flange Metal Bolts

This series of M6 12-point flange bolts combines the highest standard fastener strength class (12.9) with a selection of premium anti-corrosion coatings, offering unparalleled performance in demanding environments. The core bolt is manufactured from high-strength alloy steel, heat-treated to achieve the Grade 12.9 property class, signifying a minimum tensile strength of 1200 MPa. To protect this high-strength core from corrosion, customers can choose from advanced coatings: Dacromet, Geomet (Gumet), or Hot Dip Galvanized (HDG). This combination ensures the bolt can withstand extreme loads and severe corrosive attack simultaneously, a requirement often found in heavy industry and infrastructure.

• These heavily coated, ultra-high-strength bolts are essential for critical connections in sectors like heavy construction, wind energy, rail infrastructure, and off-highway equipment. The Grade 12.9 strength is necessary for high clamping loads in structural steel connections, heavy machinery gearboxes, and wind turbine assemblies. The selection of coating depends on the threat:

  • Dacromet/Geomet: Ideal for automotive underbody parts and applications requiring excellent corrosion resistance without the risk of hydrogen embrittlement, and with good temperature resistance.

  • Hot Dip Galvanized (HDG): The preferred choice for the most severe outdoor exposures, such as transmission towers, marine pilings, and highway infrastructure, where a thick, durable zinc layer is needed for decades of protection.

The key advantage is the combination of maximum strength (12.9) with maximum corrosion protection. Users can select the coating that best matches their environmental challenge without compromising the bolt's load-bearing capacity. These coatings, particularly Dacromet and Geomet, offer superior corrosion resistance and are free from hydrogen embrittlement, a critical safety factor for high-strength fasteners. The hot dip galvanized option provides a very thick, durable barrier for the most aggressive outdoor environments. All options retain the benefits of the 12-point flange head: high torquing capability and integrated load distribution.