Standard: NF E 25
Available sizes: ST2.2 to ST4.8 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 5282 |
| DIN | DIN EN ISO 1481 |
| ISO | ISO 1481 |
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| ST2.2 | 1.1 | 1.6 | 0.86 | 5.6 | 5.3 | 0.7 | 1.8 | 1 |
| ST2.9 | 1.4 | 2.2 | 1.26 | 8 | 7.6 | 1 | 2.4 | 1.51 |
| ST3.5 | 1.8 | 2.9 | 1.66 | 11 | 10.6 |
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.
| 1.3 |
| 3.2 |
| 1.91 |
| ST4.2 | 2.1 | 4.5 | 2.06 | 16 | 15.6 | 1.9 | 4.8 | 2.31 |
| ST4.8 | 2.1 | 5.7 | 2.56 | 20 | 19.5 | 2.4 | 6 | 2.81 |
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