Standard: GB /T 15856.4 - 1995
Available sizes: ST3.5 to ST4.8 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ST3.5 | 1.4 | 0.6 | 1.9 | 0.9 | 7 | 1.4 | 8.8 | 7.59 | 4.25 | 8.2 | 6.78 |
| ST4.2 | 1.8 | 0.8 | 2.7 | 1 | 8 | 1.8 | 11 |
| 8.71 |
| 5.45 |
| 10 |
| 7.78 |
| ST4.8 | 1.8 | 0.9 | 3.3 | 1 | 10 | 1.8 | 13.2 | 10.95 | 5.45 | 12.2 | 9.78 |
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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