Types of screws

The types of screws can be divided according to different classification standards, mainly including the following categories: screws, studs, bolts and screws. ‌

‌Ordinary screws‌: tools that use the friction of the oblique circular rotation of objects to gradually tighten objects and parts.

‌Self-tapping screws‌: hard texture, coarse teeth, pointed head, used for tapping metal holes.

‌Expansion screws‌: promote expansion through the wedge-shaped bevel, generate friction and bonding force, and achieve a fixing effect.

‌Bolts‌: The head is generally hexagonal, and the rod has external threads. It is used to connect two objects. It usually needs to pass through a light hole and be used with a nut.

‌Screws‌: smaller, with a flat head, a cross head, etc., and a rod with external threads. Usually, no nuts are required and it is directly matched with two objects.

‌Studs (double-headed studs)‌: Both ends have external threads, and the middle is generally a light rod, which is used to connect with deep holes and nuts.