Standard: CNS 4647 - 1983
Available sizes: 13 to 21 (3 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 13 | 32 | 16 | 4.45 | 5.9 | 36 | 1.6 | 0.8 | 31.5 | 1.9 | 3 |
| 17 | 44 | 22 | 6 | 8 | 50 | 2 | 1 | 81.1 | 2.5 |
| 4 |
| 21 | 56 | 27 | 6.25 | 8.5 (7.4 ①) | 56 | 2.5 | 1 | 114 | 3 | 4 (4.6 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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