First, the difference between self-tapping screws and ordinary screws Self-tapping screws and ordinary screws are common fixing tools, but there are some differences between them. First, they are different in nature. Self-tapping screws can have the characteristics of bricks, using electric facilities and equipment for construction, so that drilling, fixing and locking construction can be completed together, which is very convenient. In contrast, ordinary screws are just a universal kind of screws, except for special-shaped screws, they are ordinary screws. Secondly, their characteristics are different. Self-tapping screws can use their own threads to squeeze out the same threads on the items to be installed, so as to better fit together, and the connection is relatively tight, and it is not easy to loose. The ordinary screw is a flat head design, the thickness is the same, you need to screw eyes and tap teeth to achieve better results. Finally, the use method is also different. Self-tapping screws are usually used on non-metallic or soft metals and do not require a bottom hole or tapping. Ordinary screws need to be drilled and tapped, and are often used on harder non-metals or metals.
Second, the difference between self-tapping screws and expansion screws Expansion screws and self-tapping screws are two different fixing tools, they also have some differences. First of all, expansion screws are used to fix objects on walls, ceilings, and floors after drilling through a percussion drill. Expansion screws usually have an expansion sleeve, a screw with a taper at the bottom, a nut, a flat washer, and an elastic washer. The self-tapping screw is a kind of pointed screw, which is specially used to fix objects on thin metal plates, such as sun rooms, color plates, aluminum alloy doors and Windows. After using the drill bit to drill the bottom hole, the self-tapping screw can be directly inserted into the fixed object without tapping. In general, self-tapping screws and ordinary screws, expansion screws have different characteristics and methods of use. Choosing the right fixed tools according to different situations can help us better complete various work tasks.
