Self-Drilling Screw

A self-drilling screw is a component used in fabricated metal product manufacturing. It combines a drill-point tip with a tapping thread, allowing it to create its own pilot hole and form a mating thread in suitable sheet material without a separate drilling operation. This makes it suitable for applications such as sheet-metal roofing, cladding, HVAC, and light-gauge steel assemblies. The screw's working principle involves the drill point cutting the pilot hole, followed by the threads forming or cutting the mating thread, and finally the head clamping the sheets together. When specifying a self-drilling screw, buyers must consider several selection fields: head and drive type, thread size, drill-point capacity, clamping thickness, washer or seal, material, and coating. These parameters must be confirmed against the selected standard, drawing, and supplier evidence. The applicable standard listed in this directory is ISO 15480:2019, which covers hex-washer-head forms with nominal sizes ranging from ST2.9 to ST6.3. Materials on file include hardened steel and stainless steel by validated design. Surface finishes may include zinc-plated, coated, or specified corrosion systems. Strength and performance, including drilling capacity and torsional performance, must be confirmed for the specific application. The RFQ should state the exact standard or drawing, required configuration, quantity, and inspection evidence. Note that standards listed here govern particular forms and do not make sizes, materials, or finishes interchangeable. Always verify model-specific values and standards with the legal manufacturer or supplier before procurement.

The drill point cuts the pilot hole; following threads form or cut the mating thread and the head then clamps the sheets. This integrated action eliminates the need for a separate drill bit, improving installation efficiency. The drill-point capacity determines the maximum material thickness that can be penetrated, while the thread design ensures secure fastening. The head's clamping force holds the sheets together, and any washer or seal provides additional sealing or load distribution. Proper selection of drill-point capacity and thread size is critical to avoid failure such as stripping or inadequate clamping. The screw's performance depends on the material being fastened and the screw's material and coating. For example, hardened steel is common for general use, while stainless steel may be specified for corrosion resistance. The applicable standard, ISO 15480:2019, defines dimensional and performance requirements, but actual performance must be verified through testing or supplier documentation.