Standard: QC /T 388 - 1999
Available sizes: 10 to 8 (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 10 | 14.245 | 1 | 35 | 14.205 | 5 | 5.5 | 1 |
| 12 | 18.27 | 1 | 45 | 18.23 | 6 | 6.5 | 1 |
| 14 | 22.35 | 1.5 | 55 | 22.3 | 8 | 8.5 | 1.6 |
| 16 | 26.35 | 1.5 | 65 |
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.
| 26.3 |
| 8 |
| 8.5 |
| 1.6 |
| 18 | 30.4 | 1.5 | 75 | 30.35 | 10 | 10.5 | 1.6 |
| 20 | 32.4 | 1.5 | 80 | 32.35 | 10 | 10.5 | 1.6 |
| 8 | 10.245 | 0.7 | 25 | 10.205 | 5 | 5.5 | 1 |
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