Standard: DIN 7973 - 1990
Available sizes: (ST3.9) to ST3.5 (4 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 5284 |
| DIN | DIN EN ISO 1483 |
| ISO | ISO 1483 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (ST3.9) | 1.8 | 11.1 | 2.4 |
| 2 |
| 3.8 |
| 1.8 |
| 12.4 |
| 1.91 |
| 1.66 |
| 11.97 |
| 1.6 |
| ST2.2 | 1.1 | 4.6 | 1.1 | 0.9 | 1.7 | 1.1 | 5.5 | 1 | 0.86 | 5.2 | 0.8 |
| ST2.9 | 1.3 | 6 | 1.5 | 1.3 | 2.3 | 1.3 | 7.5 | 1.2 | 1.06 | 7.14 | 1 |
| ST3.5 | 1.6 | 8.2 | 1.9 | 1.5 | 3 | 1.6 | 9.5 | 1.51 | 1.26 | 9.14 | 1.2 |
Standard corrosion protection for indoor and mild outdoor environments.
Salt spray: 96–200 hours | RoHS compliant (trivalent chromium)
High-performance coating for automotive, marine, and harsh environments.
Salt spray: 720–1500 hours | Recommended for grade 8.8+
Heavy-duty protection for structural and outdoor applications.
Salt spray: 500–1000 hours | Thread tolerance adjustment required
Note for high-strength fasteners (Grade 10.9, 12.9): Electroplating processes require hydrogen embrittlement relief baking (minimum 4 hours at 200°C within 4 hours of plating). Contact our engineering team for grade-specific plating recommendations.
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
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