Standard: QC /T 386 - 1999
Available sizes: 12 to 8 (4 sizes)
| Size | P | k_max | s_max | s_min | k_nominal |
|---|---|---|---|---|---|
| 12 | 19.84 | 7.78 | 19.63 | 8 | 8.22 |
| 16 | 23.84 | 9.78 | 23.63 | 10 | 10.22 |
| 20 | 29.84 | 11.74 | 29.63 | 12 | 12.26 |
| 8 | 11.85 | 4.82 | 11.67 | 5 | 5.18 |
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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