Standard: QC /T 621
Available sizes: 10 to 9.5 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 10 | 13.3 | 6 | 8 | 0.77 | 8 | 12.7 | 0.8 | 7.75 | 7 | 0.83 | 8.25 |
| 10.5 | 14.3 | 6 | 8 | 0.77 | 10 | 13.7 | 0.8 | 9.75 |
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.
| 7 |
| 0.83 |
| 10.25 |
| 11 | 15.3 | 9 | 11 | 0.96 | 10 | 14.7 | 1 | 9.75 | 10 | 1.04 | 10.25 |
| 7 | 8.2 | 6 | 8 | 0.57 | 6 | 7.8 | 0.6 | 5.75 | 7 | 0.63 | 6.25 |
| 8 | 9.2 | 6 | 8 | 0.57 | 8 | 8.8 | 0.6 | 7.75 | 7 | 0.63 | 8.25 |
| 8.5 | 10.2 | 6 | 8 | 0.77 | 8 | 9.8 | 0.8 | 7.75 | 7 | 0.83 | 8.25 |
| 9 | 11.3 | 6 | 8 | 0.77 | 8 | 10.7 | 0.8 | 7.75 | 7 | 0.83 | 8.25 |
| 9.5 | 12.3 | 6 | 8 | 0.77 | 8 | 11.7 | 0.8 | 7.75 | 7 | 0.83 | 8.25 |
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