hex head screw self drilling with washer

Self-drilling hexagonal socket head cap screws, also known as dovetail screws or self-tapping screws, are a widely used and efficient fastener. They are typically equipped with EPDM washers to increase the contact surface, prevent the screw head from sinking into the fastened material, and provide a better seal to prevent loosening.

They drill directly during tightening, simultaneously creating threads in materials such as thin metal sheets, wood, and plastics, eliminating the need for pre-drilling.

Examples include the installation of color-coated steel sheets and galvanized sheets, fixing joists to partition walls and roofing systems, and assembling and securing air ducts and aluminum alloy doors and windows.

Fixing wood and composite panels: securing boards, plywood, oriented strand board (OSB), and wood frames or metal structures together, external installations and fencing, mechanical equipment, and securing billboards and signs.

The most commonly used materials for hexagonal socket head cap screws include C1022A carbon steel, thermal paste, Dacromet coating, and stainless steel (such as 304 and 316, suitable for environments requiring high corrosion resistance). Galvanizing provides basic rust protection; bright white or colored zinc coatings (blue, yellow, etc.).

Dacromet/inkjet coating: extremely corrosion resistant; silver-gray; commonly used in highly corrosive environments. We can select different production processes according to customer needs.