Screw Core Classifications:
Machine Screws: Standard threads for pre-threaded holes, with full or partial threading for precision assembly.
Self-Tapping Screws: Drill, tap, and fit without pre-drilling. Subcategories:
Ordinary Self-Tapping Screws: For plastics, wood, thin metal sheets.
Self-Drilling Screws: Drill tip pierces steel plates, no pre-drilling needed, enhancing efficiency.
Wood Screws: Deep threads, large pitch, sharp for wood, ensuring strong locking.
Set Screws: Fix parts, prevent slippage or rotation. Various ends:
Tapered End: High locking, suitable for hard surfaces.
Flat End: Large contact, non-damaging.
Concave/Cylindrical End: Positioning or pressing into shafts.
Structural screws: High-strength, heat-treated, replace bolts in steel structures, speeding installation.
Key Characteristics:
Distinct characteristics from bolts:
Mainly "tapping" or "screwing": Form thread fit, no nuts needed.
Frequent Disassembly: Secure covers, panels, for assembly/disassembly.
Size Range: From precision screws in eyewear to large self-tapping screws in structures.
High Functional Integration: Functions like drilling, tapping, locking, sealing.
Substrate Requirements: Load-bearing depends on substrate strength (plastics, wood, metal).
Typical Applications:
Screws are everywhere, spanning industrial and daily life:
Electronics and Appliances: Miniature machine/self-tapping screws for housings, circuits, components. Materials: stainless or treated carbon steel.
Machinery & Automation: Mount panels, covers, sensors, guide rails, clamps with hex/pan head screws.
Construction & Decoration:
Drywall Screws: Connect drywall to joists.
Structural Screws: Connect light steel and wood structures.
Self-Drilling Screws: Secure color steel plates and purlins.
Automotive: Various self-tapping/special screws for interiors, wiring, electronics, decor.
Furniture & Wood: Wood screws connect wood and boards like particleboard.
Precision Instruments & Watches: Miniature machine screws with high material and tolerance standards.
Aerospace: High-strength, lightweight, corrosion-resistant titanium or non-alloy screws.
