Product Specifications
| Model / Specification | ST2.2 - ST9.5 |
| Material | Carbon Steel |
| Thread | ST2.2 | ST2.9 | ST3.5 | ST4.2 | ST4.8 | ST5.5 | ST6.3 | ST8 | ST9.5 | ||
| P | Pitch | 0.8 | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | 2.1 | 2.1 | |
| a | Max. | 0.8 | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | 2.1 | 2.1 | |
| s | Max. | 3.2 | 5 | 5.5 | 7 | 8 | 8 | 10 | 13 | 16 | |
| Min. | 3.02 | 4.82 | 5.32 | 6.78 | 7.78 | 7.78 | 9.78 | 12.73 | 15.73 | ||
| e | Min. | 3.38 | 5.4 | 5.96 | 7.59 | 8.71 | 8.71 | 10.95 | 14.26 | 17.62 | |
| k | Max. | 1.6 | 2.3 | 2.6 | 3 | 3.8 | 4.1 | 4.7 | 6 | 7.5 | |
| Min. | 1.3 | 2 | 2.3 | 2.6 | 3.3 | 3.6 | 4.1 | 5.2 | 6.5 | ||
| r | Min. | 0.10 | 0.10 | 0.10 | 0.20 | 0.20 | 0.25 | 0.25 | 0.40 | 0.40 | |
| y | Ref. | Type C | 2 | 2.6 | 3.2 | 3.7 | 4.3 | 5 | 6 | 7.5 | 8 |
| Type F | 1.6 | 2.1 | 2.5 | 2.8 | 3.2 | 3.6 | 3.6 | 4.2 | 4.2 | ||
| Type R | / | / | 2.7 | 3.2 | 3.6 | 4.3 | 5 | 6.3 | / | ||
| Wt./1,000 pcs (steel) | - | - | - | - | - | - | - | - | - | ||
Hex Head Tapping Screw——Product Introduction
The hex head tapping screw is a fastener with a regular hexagonal head and a self-tapping threaded shank. It is manufactured according to GB/T 5285-2017 and is suitable for thread specifications ST2.2 to ST9.5 and product grade A. During installation, a threaded pilot hole must be pre-made in the parts to be joined. The screw uses the relatively high hardness of its thread surface to extrude a mating internal thread in the pilot hole, thereby forming a connection. The tail can be designed as a pointed tail or drill tail, suitable respectively for pre-drilled tapping and self-drilling tapping without pre-drilling.
1. Product Features
• Hex head structure: The head is a regular hexagon and can be operated with an open-end wrench, ring wrench, socket wrench or adjustable wrench, making force application convenient.
• Self-tapping thread: The thread surface has relatively high hardness and can tap an internal thread by itself in the pre-made pilot hole of the connected part, completing the connection without a mating nut.
• Pointed tail and drill tail options: The pointed tail type requires a pre-drilled pilot hole before screwing in; the drill tail type has a drill structure at the tail, completing drilling and tapping in one operation without pre-drilling.
• Wide specification coverage: Thread specifications cover ST2.2 to ST9.5, with nominal diameters from about 2.2 mm to 9.5 mm, meeting the connection needs of sheets of different thicknesses.
• Various materials and surface treatments: Common materials include carbon steel (such as 1022A) and stainless steel. Surfaces can be zinc plated and passivated, nickel plated, etc. Carbon steel 1022A is a common material for hex head tapping screws.
2. Product Advantages
• Single-side installation and high efficiency: Operation is required only from one side of the sheet, with no working space needed on the back, suitable for closed structures or assembly applications accessible from one side.
• No tapping process required: Eliminates the step of pre-tapping an internal thread, simplifying the assembly process and reducing processing costs.
• Can apply larger torque: The hex head, together with a wrench or socket, can withstand greater tightening torque than pan head tapping screws, providing a firmer connection.
• Integrated operation of drill tail type: Drill tail self-tapping screws integrate drilling, tapping and fastening, significantly shortening construction time and reducing processes and labor costs.
• Removable and adjustable: After installation, self-tapping screws can be removed and re-screwed, facilitating maintenance and component adjustment.
3. Scope of Application
• Light steel construction and color steel tiles: Fixing of steel structure factory buildings and color steel tile roofs and walls is the most typical application scenario for hex head tapping screws.
• Thin sheet metal connection: Fastening connections between steel sheets, aluminum sheets and other thin metal sheets.
• Automobile manufacturing: Self-tapping connections for automobile body sheet metal, interior parts, chassis accessories, etc.
• Home appliances and electrical appliances: Fixing of outer casings and internal components of air conditioners, refrigerators, washing machines, etc.
• General industry and construction: Thin sheet connection applications requiring rapid assembly, such as mechanical equipment housings, guards, metal doors and windows, and decorative panels.
