Description and Translation of GB/T 2670.1 Fasteners
GB/T 2670.1 fasteners, a key Chinese standard for mechanical components, function as countersunk flat head rivets widely used in machinery, electrical equipment, and sheet metal assemblies. Their primary role is to create permanent non-threaded connections, joining thin-walled components by forming a secure head through riveting, ensuring flush surface finish and reliable load transmission in applications requiring minimal protrusion.
In terms of materials, GB/T 2670.1 fasteners are predominantly manufactured from aluminum alloys (e.g., 5052, 6061) for lightweight applications, and carbon steel (e.g., Q235) for higher strength requirements. Copper and copper alloys are specified for electrical conductivity needs, while stainless steel (e.g., 304) variants provide corrosion resistance in harsh environments.
Surface treatments include anodizing for aluminum rivets to enhance corrosion resistance and wear performance, zinc plating for carbon steel variants to prevent rust, and passivation for stainless steel to maintain its anti-corrosive properties. These treatments optimize durability while ensuring compatibility with various operating conditions.
Key characteristics of GB/T 2670.1 fasteners include countersunk head designs for flush mounting, precise shank diameters, and controlled dimensional tolerances ensuring assembly accuracy. Their mechanical attributes feature appropriate shear strength (varies by material), good ductility for forming during riveting, and uniform head geometry. Additionally, they exhibit reliable permanent fastening performance and excellent vibration resistance, making them indispensable in sheet metal fabrication and mechanical assembly.
| Thread Size | ST2.9 | ST3.5 | ST4.2 | ST4.8 | ST5.5 | ST6.3 | ||||
| P | Pitch | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | |||
| a | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | ||||
| da | max | 3.5 | 4.1 | 4.9 | 5.6 | 6.3 | 7.3 | |||
| dk | max=nominal size | 5.6 | 7 | 8 | 9.5 | 11 | 12 | |||
| min | 5.3 | 6.64 | 7.64 | 9.14 | 10.57 | 11.57 | ||||
| k | max=nominal size | 2.4 | 2.6 | 3.1 | 3.7 | 4 | 4.6 | |||
| min | 2.15 | 2.35 | 2.8 | 3.4 | 3.7 | 4.3 | ||||
| r | min | 0.1 | 0.1 | 0.2 | 0.2 | 0.25 | 0.25 | |||
| R | ≈ | 5 | 6 | 6.5 | 8 | 9 | 10 | |||
| y | Ref. | Type C | 2.6 | 3.2 | 3.7 | 4.3 | 5 | 6 | ||
| Type F | 2.1 | 2.5 | 2.8 | 3.2 | 3.6 | 3.6 | ||||
| Type R | / | 2.7 | 3.2 | 3.6 | 4.3 | 5 | ||||
| Socket No. | 10 | 15 | 20 | 25 | 25 | 30 | ||||
| A | Ref. | 2.8 | 3.35 | 3.95 | 4.5 | 4.5 | 5.6 | |||
| t | max | 1.27 | 1.4 | 1.8 | 2.03 | 2.03 | 2.42 | |||
| min | 1.01 | 1.14 | 1.42 | 1.65 | 1.65 | 2.02 | ||||
Description and Translation of GB/T 2670.1 Fasteners
GB/T 2670.1 fasteners, a key Chinese standard for mechanical components, function as countersunk flat head rivets widely used in machinery, electrical equipment, and sheet metal assemblies. Their primary role is to create permanent non-threaded connections, joining thin-walled components by forming a secure head through riveting, ensuring flush surface finish and reliable load transmission in applications requiring minimal protrusion.
In terms of materials, GB/T 2670.1 fasteners are predominantly manufactured from aluminum alloys (e.g., 5052, 6061) for lightweight applications, and carbon steel (e.g., Q235) for higher strength requirements. Copper and copper alloys are specified for electrical conductivity needs, while stainless steel (e.g., 304) variants provide corrosion resistance in harsh environments.
Surface treatments include anodizing for aluminum rivets to enhance corrosion resistance and wear performance, zinc plating for carbon steel variants to prevent rust, and passivation for stainless steel to maintain its anti-corrosive properties. These treatments optimize durability while ensuring compatibility with various operating conditions.
Key characteristics of GB/T 2670.1 fasteners include countersunk head designs for flush mounting, precise shank diameters, and controlled dimensional tolerances ensuring assembly accuracy. Their mechanical attributes feature appropriate shear strength (varies by material), good ductility for forming during riveting, and uniform head geometry. Additionally, they exhibit reliable permanent fastening performance and excellent vibration resistance, making them indispensable in sheet metal fabrication and mechanical assembly.
| Thread Size | ST2.9 | ST3.5 | ST4.2 | ST4.8 | ST5.5 | ST6.3 | ||||
| P | Pitch | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | |||
| a | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | ||||
| da | max | 3.5 | 4.1 | 4.9 | 5.6 | 6.3 | 7.3 | |||
| dk | max=nominal size | 5.6 | 7 | 8 | 9.5 | 11 | 12 | |||
| min | 5.3 | 6.64 | 7.64 | 9.14 | 10.57 | 11.57 | ||||
| k | max=nominal size | 2.4 | 2.6 | 3.1 | 3.7 | 4 | 4.6 | |||
| min | 2.15 | 2.35 | 2.8 | 3.4 | 3.7 | 4.3 | ||||
| r | min | 0.1 | 0.1 | 0.2 | 0.2 | 0.25 | 0.25 | |||
| R | ≈ | 5 | 6 | 6.5 | 8 | 9 | 10 | |||
| y | Ref. | Type C | 2.6 | 3.2 | 3.7 | 4.3 | 5 | 6 | ||
| Type F | 2.1 | 2.5 | 2.8 | 3.2 | 3.6 | 3.6 | ||||
| Type R | / | 2.7 | 3.2 | 3.6 | 4.3 | 5 | ||||
| Socket No. | 10 | 15 | 20 | 25 | 25 | 30 | ||||
| A | Ref. | 2.8 | 3.35 | 3.95 | 4.5 | 4.5 | 5.6 | |||
| t | max | 1.27 | 1.4 | 1.8 | 2.03 | 2.03 | 2.42 | |||
| min | 1.01 | 1.14 | 1.42 | 1.65 | 1.65 | 2.02 | ||||
