Standard: GB 1564 - 1979
Available sizes: 10 to 8 (7 sizes)
| Size | P | k_max | s_max | s_min | k_nominal |
|---|---|---|---|---|---|
| 10 | 22 | 0.6~0.8 | 21.948 | 14 | 13.89 |
| 2 | 3 | 0.16~0.25 | 2.975 | 3 | 2.94 |
| 3 | 5 | 0.25~0.4 | 4.97 | 5 | 4.925 |
| 4 | 8 | 0.25~0.4 | 7.964 | 7 | 6.91 |
| 5 | 12 | 0.4~0.6 | 11.957 | 8 | 7.91 |
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.
| 6 | 16 | 0.4~0.6 | 15.957 | 10 | 9.91 |
| 8 | 20 | 0.6~0.8 | 19.948 | 12 | 11.89 |
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