Hexagon Flanged Self-drilling and Self-tapping Screws

The hexagon flanged self-drilling and self-tapping screw is a kind of fastener widely used in fields such as construction, machinery manufacturing, and furniture.

Standards of Hexagon Flanged Self-drilling and Self-tapping Screws:

The current standard is "GB/T 15856.5-2023 Hexagon Flanged Self-drilling and Self-tapping Screws", which was issued by the State Administration for Market Regulation and the National Standardization Administration on May 23, 2023, and implemented on December 1, 2023. This standard specifies the type dimensions, technical requirements, marking labels, and markings of hexagon flanged self-drilling and self-tapping screws, and is applicable to hexagon flanged self-drilling and self-tapping screws with a thread specification of ST2.9 to ST6.3, made of steel, and with a product grade of A.

Structural Features of Hexagon Flanged Self-drilling and Self-tapping Screws:

Hexagon Flanged Head: The head is hexagonal, which is convenient for tightening and disassembling with tools such as wrenches and can provide a large torque application area. At the same time, it has a flange. The flange increases the contact area with the surface of the connected component, can disperse the pressure, prevent damage to the surface of the connected component, and improve the sealing performance and anti-loosening performance of the connection.

Self-drilling Function: The front end of the screw has a cutting edge in the shape of a drill bit. During installation, there is no need to pre-drill a hole, and it can directly drill a suitable hole in the material and continue to screw in to form a threaded connection, which improves the installation efficiency and is especially suitable for on-site construction or situations where pre-drilling is difficult.

Self-tapping Thread: The thread part adopts a special tooth profile design, and can extrude an internal thread on the material of the connected component by itself during the screwing-in process. It closely matches the material of the connected component, has high connection strength, can effectively prevent the screw from loosening, and ensure the reliability of the connection.

Materials and Surface Treatments of Hexagon Flanged Self-drilling and Self-tapping Screws:

Materials: Usually made of carbon steel or alloy steel. Carbon steel materials have high strength and hardness, can meet the connection strength requirements of general engineering applications, and have a relatively low cost. Alloy steel materials have better comprehensive performance and can be used in occasions with higher performance requirements.

Surface Treatments: Common surface treatments include galvanizing, nickel plating, etc. Galvanizing treatment can improve the corrosion resistance of the screws; nickel plating treatment can not only enhance the corrosion resistance but also make the surface more beautiful and smooth. These surface treatments can be selected according to the usage environment and specific requirements to improve the service life and performance of the screws.

Specifications and Dimensions of Hexagon Flanged Self-drilling and Self-tapping Screws:

The thread specifications include ST2.9, ST3.5, ST4.2, ST4.8, ST5.5, ST6.3, etc. The length dimensions vary according to different specifications and usage requirements, generally ranging from 16mm to 100mm. For example, for connecting thinner materials, screws with a length of 20mm or 30mm may be selected; while for connecting multiple layers of thick materials or situations where it is necessary to penetrate thicker materials, longer screws, such as 50mm, 80mm or even longer specifications, need to be selected.

Application Fields of Hexagon Flanged Self-drilling and Self-tapping Screws:

Construction Industry: In steel structure buildings, it is used to connect components such as section steels and steel plates, such as the connection of roof trusses, purlins, wall beams, etc. In the installation of building curtain walls, it can connect and fix the curtain wall frame to the main structure.

Machinery Manufacturing: It is used for the connection of parts and components of mechanical equipment, such as the assembly of cases and cabinets. It can quickly connect thin plate materials and has good vibration resistance, ensuring the firmness of the equipment structure during operation.

Furniture Manufacturing: It is commonly used in the connection of metal furniture or panel furniture with metal accessories. For example, it can connect components such as table legs and chair backs to the frame, and fix the hardware connectors to the panels, enhancing the structural stability of the furniture.

Installation Precautions for Hexagon Flanged Self-drilling and Self-tapping Screws:

Select Appropriate Tools: Use electric or manual tools that match the screw specifications, such as electric screwdrivers, pneumatic wrenches, etc. Ensure that the tools can provide sufficient torque, but avoid excessive torque causing the screw to break or damaging the connected component.

Control the Drilling Depth: Although it has a self-drilling function, it is still necessary to control the drilling depth according to the thickness of the connected component to avoid the drill bit penetrating the bottom material or the drilling being too shallow, which will prevent the thread from being fully formed and affect the connection strength.

Pay Attention to the Installation Angle: During installation, keep the screw perpendicular to the surface of the connected component to ensure that the screw can smoothly drill into the material and form a uniform thread, and avoid damage to the thread or insecure connection caused by angle deviation.

Avoid Over-tightening: When the flange of the screw head is closely attached to the surface of the connected component and reaches the specified torque value, the installation can be considered completed. Do not over-tighten it any more to avoid deforming the flange or damaging the material of the connected component.