Standard: GB /T 3390.1 - 2013
Available sizes: 3.2 to 5 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 3.2 | 4 | 2.4 | 26 | 2.1 | 6.9 | 10.4 | 12.5 | 45 |
| 4 | 5 | 3 | 26 | 2.4 | 8.2 | 15.1 | 12.5 | 45 |
| 4.5 | 6 | 4 | 26 | 3.1 |
| 9.4 |
| 20.6 |
| 12.5 |
| 45 |
| 5 | 8 | 6 | 26 | 4.24 | 12.2 | 33.6 | 12.5 | 45 |
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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