Description and Translation of DIN 7504 Fasteners
DIN 7504 fasteners, a specialized German standard for automotive and industrial hardware, function as hexagon weld nuts designed for permanent installation in sheet metal and structural components. Their primary role is to create robust threaded connections in welded assemblies, providing reliable clamping points for bolts in automotive bodies, machinery frames, and metal structures. These nuts facilitate efficient assembly by eliminating the need for pre-drilled threads, ensuring strong load transmission in welded joints.
In terms of materials, DIN 7504 fasteners are predominantly manufactured from low-carbon steel (e.g., DC04 and St37-2 per DIN standards) optimized for welding compatibility. This material ensures good weldability, minimal spatter formation, and sufficient mechanical strength after welding. For corrosion-resistant applications, zinc-coated low-carbon steel variants are specified to enhance durability in humid or mild chemical environments.
Surface treatments include zinc plating with chromate passivation for improved corrosion resistance, phosphate coating to facilitate welding processes, and thin organic coatings for temporary rust protection during storage and transportation. These treatments optimize weldability while extending service life in operational environments.
Key characteristics of DIN 7504 fasteners include standardized metric threads, hexagonal profiles with weld projections, and precise dimensional tolerances ensuring welding accuracy. Their mechanical attributes feature appropriate tensile strength (minimum 300 MPa) post-welding, good ductility to absorb welding stresses, and uniform thread geometry. Additionally, they exhibit consistent weld strength and reliable thread performance, making them indispensable in automotive manufacturing and metal structure 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 | max | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | |
| dk | max | 5.6 | 7 | 8 | 9.5 | 11 | 12 | |
| min | 5.3 | 6.64 | 7.64 | 9.14 | 10.57 | 11.57 | ||
| k | max | 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 | |
| dp | 2.3 | 2.8 | 3.6 | 4.1 | 4.8 | 5.8 | ||
| Drilling range(thickness) | 0.7~1.9 | 0.7~2.25 | 1.75~3 | 1.75~4.4 | 1.75~5.25 | 2~6 | ||
| Socket No. | 1 | 2 | 2 | 2 | 3 | 3 | ||
| M1 | 3 | 3.9 | 4.4 | 4.9 | 6.4 | 6.9 | ||
| M2 | 3 | 4 | 4.4 | 4.8 | 6.2 | 6.8 | ||
| Lg (min.) | - | |||||||
| ①,Material: Be made of either of case hardening steel as specified in DIN 172100 or steel for quenching and tempering as specified in DIN EN 10083-1 and DIN EN 10083-2 (at the manufacturer's discretion), use of steel grades of equivalent quality being permitted | ||||||||
Description and Translation of DIN 7504 Fasteners
DIN 7504 fasteners, a specialized German standard for automotive and industrial hardware, function as hexagon weld nuts designed for permanent installation in sheet metal and structural components. Their primary role is to create robust threaded connections in welded assemblies, providing reliable clamping points for bolts in automotive bodies, machinery frames, and metal structures. These nuts facilitate efficient assembly by eliminating the need for pre-drilled threads, ensuring strong load transmission in welded joints.
In terms of materials, DIN 7504 fasteners are predominantly manufactured from low-carbon steel (e.g., DC04 and St37-2 per DIN standards) optimized for welding compatibility. This material ensures good weldability, minimal spatter formation, and sufficient mechanical strength after welding. For corrosion-resistant applications, zinc-coated low-carbon steel variants are specified to enhance durability in humid or mild chemical environments.
Surface treatments include zinc plating with chromate passivation for improved corrosion resistance, phosphate coating to facilitate welding processes, and thin organic coatings for temporary rust protection during storage and transportation. These treatments optimize weldability while extending service life in operational environments.
Key characteristics of DIN 7504 fasteners include standardized metric threads, hexagonal profiles with weld projections, and precise dimensional tolerances ensuring welding accuracy. Their mechanical attributes feature appropriate tensile strength (minimum 300 MPa) post-welding, good ductility to absorb welding stresses, and uniform thread geometry. Additionally, they exhibit consistent weld strength and reliable thread performance, making them indispensable in automotive manufacturing and metal structure 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 | max | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | |
| dk | max | 5.6 | 7 | 8 | 9.5 | 11 | 12 | |
| min | 5.3 | 6.64 | 7.64 | 9.14 | 10.57 | 11.57 | ||
| k | max | 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 | |
| dp | 2.3 | 2.8 | 3.6 | 4.1 | 4.8 | 5.8 | ||
| Drilling range(thickness) | 0.7~1.9 | 0.7~2.25 | 1.75~3 | 1.75~4.4 | 1.75~5.25 | 2~6 | ||
| Socket No. | 1 | 2 | 2 | 2 | 3 | 3 | ||
| M1 | 3 | 3.9 | 4.4 | 4.9 | 6.4 | 6.9 | ||
| M2 | 3 | 4 | 4.4 | 4.8 | 6.2 | 6.8 | ||
| Lg (min.) | - | |||||||
| ①,Material: Be made of either of case hardening steel as specified in DIN 172100 or steel for quenching and tempering as specified in DIN EN 10083-1 and DIN EN 10083-2 (at the manufacturer's discretion), use of steel grades of equivalent quality being permitted | ||||||||
