Self Tapping Nuts For Metal

The self-tapping nut forms a tight thread fit with the plate and has high pull-off resistance. When an M6 self-tapping nut is installed on a 2.0 mm thick ordinary steel plate, the minimum axial pull-out force can reach 1800 N (approximately 183 kgf). This data means that the nut will not pull out of the plate even under large tensile loads. This advantage is critical for applications where heavy loads need to be suspended or subjected to vibrations (e.g. electrical control boxes, vehicle interior panels).

High-quality self-tapping nuts adopt precise trilobular thread geometry, and the installation torque range is narrow and controllable. Taking M6 as an example, it is recommended that the installation torque is 8~12 N·m, and there is a clear safety window between the failure torque (≥12 N·m). The installation torque window of general products is only 5 to 8 N·m, which can easily exceed the breaking torque and cause tooth slipping. When using pneumatic tools with torque control, the CpK process capability index of high-quality products can reach more than 1.33, ensuring that every nut is installed reliably.

Self-tapping nuts are designed to fit standard screwdriver bits or sockets (hexagonal flange or round groove). It was measured that an ordinary 1000 rpm pneumatic screwdriver was used to install an M5 self-tapping nut. After working continuously for 8 hours, the tool wear was equivalent to that of traditional nuts, without the need for special equipment. In addition, its installation torque window is as wide as 4 N·m, allowing ordinary torque control tools to be easily used without the need for high-precision servo tightening shafts, which lowers the threshold for equipment purchase.

Carbon steel or stainless steel self-tapping nuts engage sheet metal tightly to create a low-resistance connection. Tests have shown that when an M6 self-tapping nut is installed on a 2.0 mm galvanized steel plate, the contact resistance stabilizes below 0.5 mΩ (measured using a microohmmeter). This performance meets the grounding requirements for electrical equipment (standards usually require ≤ 0.1 Ω). In contrast, when using a regular nut plus flat washer combination, the contact resistance is susceptible to loosening and oxidation and may rise to over 5 mΩ. Self-tapping nuts provide reliable electrical continuity.

No sparks during installation

• Welding nuts requires arc or resistance welding, which can produce sparks. Self-tapping nuts are purely mechanically installed, with a spark rate of 0, and are suitable for flammable and explosive environments (such as gas stations, chemical plants, mines).

Does not damage the plate coating

• Welding nuts can ablate paint or plating on the back, with damage up to 10 mm in diameter. Self-tapping nuts do not generate high temperatures when installed and do not affect the existing anti-corrosion or decorative coating on the back at all.

Supports multiple drive geometries

• Self-tapping nuts can provide a variety of driving forms such as hexagonal, hexagonal flange, cross recessed, and internal hexagonal. For example, the T40 internal hexagonal drive can withstand a torque of 15 N·m without sliding grooves and is adaptable to different assembly tools.

Connecting boards of different thicknesses

• A self-tapping nut can fix multiple layers of metal plates at the same time, and can effectively form threads within the total thickness range of 0.8 to 4.0 mm. No need to change nut sizes for different thickness combinations.