Screw Core Classifications:
Machine Screws: Standard threads for pre-machined holes. Threaded shank for assembly.
Self-Tapping Screws: Drill, tap, push in without pre-drilled holes. Subcategories include:
Ordinary Self-Tapping Screws: For plastics, wood, thin metal.
Self-Drilling Self-Tapping Screws: Drill tip cuts steel, saves pre-drilling time.
Wood Screws: Deep threads, sharp teeth ensure strong locking in wood.
Set Screws: Fix positions, stop slippage/rotation with varied end shapes:
Tapered End: High locking force on hard surfaces.
Flat End: Large contact area without damage.
Concave/Cylindrical End: For positioning or shaft hole pressing.
Structural screws: High-strength, heat-treated, replace bolts, speed installation.
