The hexagon socket large flat head screw is a fastener with a hexagon socket hole design on the head and a flat or flat top. It needs to be used with a hexagon socket wrench.
1. Features ‌
Hexagon socket hole design‌: The head needs to be operated with a hexagon socket wrench of the corresponding specification. It is not easy to slip during installation and is suitable for scenes with limited space. ‌
Flat head structure‌: The ultra-thin flat head design makes it flush with the contact surface after installation, and the appearance is neat and beautiful, especially suitable for occasions with high requirements for surface flatness. ‌
High-strength material‌: Common materials include 304/410 stainless steel (corrosion-resistant) and carbon steel (strong economy). Some products can reach 12.9 grade high strength, suitable for high-load environments. ‌
2. Standards and specifications ‌
National standard‌: ‌GB/T 70.2‌: Covers the size and technical requirements of hexagon socket flat round head screws, suitable for general mechanical connections. ‌
‌GB/T 70.4‌: Specifies hexagon socket flat round head screws with flanges (washers) to enhance preload. ‌International standards‌: ‌ISO 7380 series‌: Includes flat round head and washer models, suitable for international general equipment‌. ‌JIS B 1174‌: Japanese industrial standard, including a washer design version‌. ‌
Model example‌: For example, ‌YJT 4026‌ is a typical large flat head screw model that meets the high strength requirements of multiple scenarios‌.
3. Application scenarios ‌
Furniture assembly‌: Used to connect wooden or metal parts, taking into account both stability and aesthetics, such as cabinets and baby cribs. ‌
Machinery manufacturing‌: Suitable for connecting parts of machine tools, automobiles and other equipment, and the 12.9 grade high-strength model can withstand extreme pressure‌. ‌
Construction engineering‌: Used for the installation of outdoor facilities such as steel structures and billboards, and the stainless steel material has excellent weather resistance‌.
IV. Purchase suggestions
1. Material selection: 304/316 stainless steel (rust-proof) is preferred for humid environments; carbon steel or galvanized materials (cost-effective) are optional for conventional environments.
2. Strength matching: 12.9 grade is suitable for heavy-duty machinery; 8.8 grade meets general industrial needs.
3. Specification parameters: The thread length needs to be selected according to the thickness of the connector (such as M5×20 means diameter 5mm, length 20mm)