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.

Advanced Technical Specifications & Performance

Engineered for high-stress industrial applications, our hex head self-drilling screws deliver exceptional driving performance and strip-out resistance. Manufactured from premium heat-treated C1022A carbon steel, these fasteners feature a precisely formed drill point (Tek point) that allows for simultaneous drilling, tapping, and fastening into structural steel studs without pre-drilling.

Precision-Formed Drill Point: Available in #3 and #5 drill points, enabling smooth penetration through cold-rolled steel sheets and heavy structural purlins up to 12mm thickness seamlessly.

Premium EPDM Bonded Washer: The vulcanized rubber layer provides excellent elasticity, sealing the penetration hole completely to prevent water leaks and handle extreme thermal expansion or contraction in outdoor roofing systems.

Superior Surface Anti-Corrosion Options:Choose from high-grade Yellow/White Zinc Plated, Ruspert coating, or Mechanical Galvanizing to meet rigorous salt-spray testing requirements (ranging from 24 to over 1000 hours) based on your project environment.

Global Supply Chain & OEM Factory Solutions

As a professional fastener manufacturer based in China, we fully support your wholesale and importing requirements:

Customized Packaging: Bulk 25kg export cartons, heavy-duty woven bags, or small branded boxes (500 or 1000 pcs/box) featuring your company logo and barcodes.

Rigorous Testing: Every batch is subject to strict torque tests, core hardness evaluation, and drilling speed checks to eliminate head-snapping or blunt point issues before shipping.