Standard: UNI 7347 - 1974
Available sizes: 1.5 to 3.5 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 1.5 | 3.6 | 1.6 | 1.52 | 3.42 | 1.9 | 1.82 | 0.838 |
| 1.9 | 5.35 | 2.43 | 2.33 | 5.17 | 2.94 | 2.85 | 1.08 |
| 2.5 | 7.25 | 3.2 | 3.1 | 7.03 | 3.91 | 3.81 | 1.26 |
| 2.9 |
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.
| 9.1 |
| 3.8 |
| 3.7 |
| 8.88 |
| 4.62 |
| 4.49 |
| 1.5 |
| 3.5 | 11.6 | 5.13 | 5.02 | 11.33 | 6.14 | 5.99 | 1.78 |
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