Hex Head Self-Drilling Screw

Hexagon head self-drilling screws are manufactured in accordance with GB/T15856.4‑2002 standard. Made of high-quality SWRCH22A cold heading steel with Grade A quality. Equipped with self-drilling function, no pre-drilling required. It can complete drilling, tapping and locking in one single operation for efficient and convenient assembly. Widely used for fastening connections of color steel tiles, steel structure purlins, metal sheets, steel structure enclosures and other applications.

Product Parameters

Standard No.: GB/T15856.4‑2002 Material: SWRCH22A Product Grade: Grade A Head Type: Hexagon Head (Type A Recess) Thread Specification: A Screw Diameter: 4.8mm Regular Sizes: 4.8×20, 4.8×30, 4.8×40; screw length can be customized Surface Treatment: Galvanized for enhanced rust and corrosion resistance, suitable for outdoor and humid working conditions Nominal Length: Customizable upon request (special lengths such as 220 are available)

Stock Size 4.8×20: 7,000 pcs per carton, packed in 10 boxes. 10 matching sockets will be provided free of charge with purchase for easier installation and removal.

Product Advantages

Base material SWRCH22A with excellent overall performance Adopting SWRCH22A cold heading steel wire, the material features good toughness and moderate hardness. The drill point is sharp, resistant to point breaking and screw fracture. It delivers good anti-vibration and anti-loosening performance with Grade A precision and well-formed threads.

Galvanized anti-corrosion treatment Overall galvanization with uniform coating and strong adhesion, effectively resisting erosion from rain and moisture. Ideal for long-term service in outdoor steel structure and color steel projects to delay rusting and aging.

Hexagon Head with Type A Recess for stable force bearing This head design fits socket tools, offering large bearing area and uniform stress during tightening, preventing slipping. It enables convenient assembly and disassembly and is compatible with power tools for mass installation.

Self-drilling tail, no pre-drilling required Built-in self-drilling cutting function; drilling, tapping and locking can be finished in one step. Pre-drilling work is eliminated to greatly improve on-site construction efficiency. Suitable for fastening thin metal sheets, steel purlins and color steel panels.

Flexible specifications & non-standard customization Sizes 4.8×20, 4.8×30 and 4.8×40 are kept in stock. Screw lengths and types can be customized as required, including special nominal lengths like 220, to meet special working conditions of various projects.

Application Scope

✅ Fastening for roof and wall color steel tiles & panels ✅ Installation of purlins and enclosure systems for steel structure workshops ✅ Joint fixing of thin metal sheets and galvanized plates ✅ Fastening for steel structure projects, fences, guardrails and auxiliary photovoltaic components ✅ Renovation of workshops and supporting fastening for outdoor steel structures

Usage Notes

Use with electric socket tools. Matching sockets are recommended to prevent slipping and damage to screw heads. Suitable for metal substrates of corresponding thickness. Do NOT use on extra-thick hard steel to avoid damage to the drill point. Store in dry and ventilated environment. Avoid long-term stacking in humid conditions which may impair the galvanized anti-rust layer.

Packaging & Supply

Production of non-standard custom lengths can be arranged as requested. Bulk supply for engineering projects is available.