I. Application Fields & National Standard Basis

This product is strictly manufactured under the national standard GB/T15856.2-2002. Featuring a 90° Phillips countersunk head structure, the screw head fully sinks into panels after tightening to deliver a smooth, bump-free surface.

It is widely applied to light steel keel suspended ceilings, door and window hardware, interior sheet metal parts, light steel frames, sheet metal furniture connectors and aluminum alloy auxiliary component assembly. Large quantities of our products are exported all year round to overseas hardware and building materials markets in the Middle East, Southeast Asia, Africa and other regions.

Equipped with an integrated drilling tip, pre-drilling is unnecessary. It can drill through thin steel sheets and self-tap into wood panels for dual-purpose application.

II. Raw Materials & Production Processes

High-quality carbon steel is adopted as raw material and subject to overall quenching heat treatment. The cutting edge of the drill tip meets standard hardness requirements for sharp drilling performance, effectively preventing tip chipping and tail breakage during drilling.

The complete production workflow includes eleven procedures: raw material rough drawing, annealing, phosphating, fine drawing, cold heading, tail forming, thread rolling, thermal refining treatment, galvanizing, washer assembly and packaging.

Standardized Phillips slot fits universal Phillips screwdriver bits, avoiding slipping and slot cracking during installation. Thread pitch complies with national standard parameters to form tight engagement with substrates, resisting loosening under long-term vibration conditions. The blue zinc electroplating coating is dense and uniform.

III. Core Product Advantages

90° Concealed Countersunk Installation: The tapered countersunk head sits flush with workpieces after fastening without exposed protrusions, making it the top choice for interior decoration and home renovation projects with strict flatness requirements.

National Standard Dual-Purpose Self-Drilling Performance: Fully compliant with national standard drilling parameters, it directly drills 0.7–6mm cold-rolled steel sheets and galvanized iron sheets, and fits fastening of solid wood, MDF and plastic parts, reducing customers’ inventory varieties.

IV. Quality Control, Warehousing & Supporting Services

All standard sizes conforming to national standards are kept in permanent stock. Standard orders can be dispatched within 48 hours. We accept small-batch trial orders as well as full-container bulk export orders.

Prior to delivery, every batch undergoes item-by-item sampling inspection in line with national standards, covering drill tip hardness, cross slot strength, thread precision and coating adhesion to eliminate defective products such as cracked heads and incomplete threads.

Matching flat washers and spring washers produced in our factory can be bundled into complete sets to provide one-stop supply of fastener accessories. Custom non-standard self-drilling screws with extended shanks and special shapes are available per customer drawings and samples. Stable production capacity ensures long-term repeat orders for overseas clients.