Standard: CNS 4645 - 1983
Available sizes: 3.2 to 7.4 (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 3.2 | 4 | 0.251 | 3.5 | 8 | 13 | 0.38 |
| 3.7 | 6 | 0.55 | 5 | 10 | 16 | 0.5 |
| 4.3 | 7 | 0.9 | 7 | 14 | 18 | 0.5 |
| 5.3 | 10 | 2.51 | 10 |
| 21 |
| 22 |
| 0.75 |
| 6.4 | 12 | 5.09 | 14 | 28 | 28 | 1 |
| 7.4 | 18 | 8.24 | 18 | 34 | 36 | 1 |
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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