M18 M22 Hdg Hot Dig Galvanized Dacromet Geomet Hex Socket Head Machine Metal Screw Din912 Grade 4.8 8.8 10.9 12.9

M18 M22 Hdg Hot Dig Galvanized Dacromet Geomet Hex Socket Head Machine Metal Screw Din912 Grade 4.8 8.8 10.9 12.9

These large-diameter hex socket head cap screws are available in M18 and M22, designed for heavy-duty and highly corrosive environments. Material: carbon or alloy steel with property classes 4.8, 8.8, 10.9, or 12.9. Surface finishes include three high-performance options: Hot Dip Galvanized (HDG), Dacromet, and Geomet. HDG provides a thick zinc layer (40-70μm) for outdoor steel structures; Dacromet and Geomet are chromium-free zinc-aluminium coatings offering excellent salt spray resistance (up to 1000 hours) with no hydrogen embrittlement risk. Head conforms to DIN912, allowing high torque via large hex keys.

Wind turbine tower flange connections – Grade 12.9 + Dacromet for cyclic loads.

Bridge seismic stoppers – HDG provides 30+ years rust protection.

Chemical reactor manways – Geomet coating resists acid mist.

Mining machinery chassis – M22 high-strength bolts.

Port crane rail clips – HDG resists seawater.

Large diameters, high load capacity – M18/M22 for heavy connections.

Multiple strength grades – from 4.8 to 12.9 for design flexibility.

Premium anti-corrosion coatings – HDG, Dacromet, Geomet for various aggressivity levels.

No hydrogen embrittlement – Dacromet/Geomet safe for high-strength bolts.

DIN912 standard – hex drive allows very high torque transmission.