1. Different uses of expansion screws and self-tapping screws
Expansion screws are mainly used to fix steel components, rails, and steel partitions, etc., and form a tight connection after expansion. Self-tapping screws are often used to fix wooden structures and thin steel plates without pre-punching.
2. Different materials of expansion screws and self-tapping screws
Expansion screws are usually made of high-quality steel or stainless steel to ensure their strength and corrosion resistance; while self-tapping screws are usually made of carbon steel or galvanized steel.
3. Different installation methods of expansion screws and self-tapping screws
Expansion screws need to be drilled first, then the screws are inserted into the holes, and then the nuts are rotated to expand the screw heads outward and finally fixed on the surface of the object. Self-tapping screws are cut by spirals, directly pass through the object, and fix themselves on the surface of the object.
4. Different scopes of application of expansion screws and self-tapping screws
Expansion screws are suitable for relatively strong materials, such as concrete, steel structures, etc. Self-tapping screws are suitable for relatively soft materials, such as wood, fiberglass, etc.
