Differences between self-tapping screws and self-drilling screws
What is a self-drilling screw?
Drilling screws can also be called dovetail screw, the tail is like the tail of a swallow, the tail of which is drill-tailed or pointed-tailed. No auxiliary processing is required. Drilling, tapping, and locking can be made directly on the setting materials and basic materials, which greatly saves construction time.
What is a self-tapping screw?
Self-tapping screws, or quick-tooth screws, are quick-fitting fasteners made of steel and passivated with galvanized surfaces. You can use Self-tapping screws for connection between thin metal plates (steel plates, sawn plates, etc). When connecting, first predrill a threaded bottom hole for the connected piece, and then screw the self-tapping screw into the threaded bottom hole of the connected piece.
- The difference in use: self-tapping screws are used on non-metallic or softer metals (such as color steel plates) and other materials with low hardness. It can create the corresponding threads for fixed objects by drilling, squeezing, pressing, and tapping, moreover make them closely matched. The self-drilling screws are mainly used for fixing color steel tiles of steel structures and thin plates.
- The difference in usage: when you screw in the self-tapping screw, the corresponding internal thread is formed by extrusion. No drilling or tapping is required, and you can finish the operation at one time. But it is not recommended to drill multiple times as it is easy to damage the drilling or slide the wire. When using the self-drilling screws, there is no need for auxiliary processing, and drilling, tapping, locking, etc. All jobs can be completed on the material at one time, which greatly saves the installation time.
- The difference in appearance: self-tapping screws are generally pointed, coarse-toothed, harder, with a certain degree of taper, so that they can be “self-tapping”, but they cannot be drilled. For self-drilling screws,there is a drill bit that can be drilled.