Screw Core Classifications:
Machine Screws: Standard threads (metric, imperial) for pre-machined holes. Fully or partially threaded, perfect for precision assembly.
Self-Tapping Screws: Drill, tap, push sans pre-drilled holes. Subcategories include:
Ordinary Self-Tapping Screws: For plastics, wood, thin metal.
Self-Drilling Self-Tapping Screws: Drill tip pierces steel, no pre-drilling, boosts efficiency.
Wood Screws: Deep threads, sharp teeth for wood, strong lock.
Set Screws: Fix positions, prevent slippage. Various end shapes:
Tapered End: High lock force, suits hard surfaces.
Flat End: Large contact, non-damaging.
Concave/Cylindrical End: For positioning or shaft holes.
Structural screws: High-strength, heat-treated, replace bolts in steel, speed install.