Standard: QC /T 621
Available sizes: 10 to 9.5 (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 10 | 13.8 | 1.57 | 15 | 13.2 | 1.6 | 14 | 1.63 | 16 |
| 11.2 | 14.3 | 1.57 | 15 | 13.7 | 1.6 | 14 | 1.63 | 16 |
| 6.5 | 7.2 | 0.78 | 12 | 6.8 |
| 0.8 |
| 11 |
| 0.82 |
| 13 |
| 7 | 9.7 | 1.17 | 12 | 9.3 | 1.2 | 11 | 1.23 | 13 |
| 8.5 | 11.5 | 1.57 | 12 | 10.9 | 1.6 | 11 | 1.63 | 13 |
| 9.5 | 12.3 | 1.57 | 15 | 11.7 | 1.6 | 14 | 1.63 | 16 |
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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