Standard: UNI 7437 - 1975
Available sizes: 10 to 9 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 10 | 1 | 14.1 | 14.46 | 0.94 | 3.6 | 1.5 | 0.42 | 1.8 | 13.92 |
| 11 | 1 | 16.2 | 16.56 | 0.94 | 3.7 | 1.7 | 0.56 | 2 | 16.02 |
| 12 |
| 1 |
| 18.3 |
| 18.72 |
| 0.94 |
| 3.9 |
| 1.7 |
| 0.65 |
| 2.1 |
| 18.09 |
| 13 | 1 | 20.5 | 20.92 | 0.94 | 4.1 | 2 | 0.83 | 2.2 | 20.29 |
| 14 | 1 | 22.5 | 22.92 | 0.94 | 4.2 | 2 | 1 | 2.4 | 22.29 |
| 15 | 1 | 23.5 | 23.92 | 0.94 | 4.2 | 2 | 1.1 | 2.5 | 23.29 |
| 8 | 0.8 | 9.8 | 10.16 | 0.74 | 2.5 | 1 | 0.15 | 1.3 | 9.62 |
| 9 | 1 | 11.8 | 12.16 | 0.94 | 3.3 | 1.2 | 0.31 | 1.5 | 11.62 |
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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