Standard: CNS 4255 - 1978
Available sizes: 3 to 8 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 4.1 | 1.75 | 2.5 | 3.5 | 4.2 | 6.7 | 9 | 3.2 | 3.9 | 8.7 | 2.8 |
| 4 | 6.1 | 2.25 | 3.2 | 4.5 | 5.4 | 9.5 | 12 | 4.1 | 5 | 11.6 | 3.6 |
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.
| 5 |
| 10.2 |
| 3 |
| 4.2 |
| 6 |
| 7.2 |
| 15 |
| 19 |
| 5.4 |
| 6.6 |
| 18.5 |
| 4.8 |
| 6 | 14.2 | 4.5 | 6.4 | 9 | 10.8 | 21 | 27 | 8.2 | 10 | 26.5 | 7.2 |
| 8 | 18.2 | 5.5 | 8 | 11 | 13.2 | 27 | 34 | 10.2 | 12.4 | 33.5 | 8.8 |
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