Standard: GB /T 97.5
Available sizes: ST2.2 to ST4.8 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 97.5(N) |
| DIN | DIN EN ISO 10669(N) |
| ISO | ISO 10669(N) |
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| ST2.2 | 2.5 | 1 | 1.06 | 2.6 | 7 | 0.264 | 6.64 |
| 0.94 |
| ST2.9 | 3.55 | 1 | 1.06 | 3.67 | 9 | 0.422 | 8.64 | 0.94 |
| ST3.5 | 4.7 | 1.6 | 1.68 | 4.82 | 12 | 1.2 | 11.57 | 1.52 |
| ST4.2 | 7.15 | 1.6 | 1.68 | 7.3 | 16 | 2.02 | 15.57 | 1.52 |
| ST4.8 | 8.8 | 2 | 2.09 | 8.95 | 20 | 3.98 | 19.48 | 1.91 |
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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