Self-tapping screws are used for non-metallic materials or too soft metal materials, without inner holes and tapping; self-tapping screws are pointed, so that they can be "self-tapping"; ordinary screws are all round heads and the size is the same. Self-tapping screws mean that the drilled hole is a hole that does not need to be tapped, and the screws used are different from the general ones. The head is long and pointed, and the tooth distance is relatively large, which is somewhat similar to a chip-free tap. You can screw in immediately without tapping. Metal materials and plastics usually use these methods.

It can "tap-drill, squeeze, and press" the preloaded body out of the corresponding thread on the prepressed material and rely on its own thread to make it cooperate with each other.

Self-tapping screws are screws containing twist drills. According to the special pneumatic tool engineering construction, drilling, tapping, fixing and clamping are carried out at one time. Self-tapping screws are mainly used for the access and fixation of some metal sheet parts, such as the connection between color steel tiles and color steel plates, the connection between color steel tiles and steel purlins, wall beams, etc. The penetration capacity is generally not more than 6mm, and the larger is not more than 12mm. Self-tapping screws are often exposed outdoors and have strong corrosion resistance; their silicone sealing rings can ensure that the screws do not leak and have good corrosion resistance. Self-tapping screws are usually described by three main parameters: the equal ratio of screw aperture, the total number of threads per foot, and the length of the screw. There are two types of screw aperture equal ratio series: 10 and 12, and the matching screw aperture is 4.87mm and 5.43mm respectively; the total number of threads per foot has three grades: 14, 16, and 24. The more the total number of threads per foot, the stronger the self-drilling ability.