Standard: GB /T 5646 - 2008
Available sizes: 10 to 8 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 10 | 20 | 6.8 | 6.5 | 21.87 | 27.5 | 20.25 | 20.15 | 24.9 | 24.4 | 22 | 27.3 |
| 12 | 25 | 7.3 | 7 | 26.87 | 33.5 | 25.25 | 25.15 | 30.9 | 30.4 | 27 | 33.3 |
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.
| 14 | 32 | 7.8 | 7.5 | 33.84 | 39.5 | 32.3 | 32.2 | 36.9 | 36.4 | 34 | 39.3 |
| 16 | 34 | 7.8 | 7.5 | 35.84 | 42.5 | 34.3 | 34.2 | 39.9 | 39.4 | 36 | 42.3 |
| 4 | 5 | 3.8 | 3.5 | 6.41 | 8.7 | 5.25 | 5.15 | 7.2 | 6.7 | 6.5 | 8.5 |
| 5 | 8 | 4.8 | 4.5 | 9.41 | 12.2 | 8.25 | 8.15 | 10.4 | 9.9 | 9.5 | 12 |
| 6 | 12 | 4.8 | 4.5 | 13.39 | 16.2 | 12.25 | 12.15 | 14.4 | 13.9 | 13.5 | 16 |
| 8 | 16 | 4.8 | 4.5 | 17.87 | 22.2 | 16.25 | 16.15 | 19.9 | 19.4 | 18 | 22 |
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