Standard: UNI 9709 - 1990
Available sizes: 3 to 4.5 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 3.65 | 2.4 | 2.6 | 2.15 | 1.85 | 3.35 | 2.89 | 1.8 | 2.5 | 2.59 | 2 |
| 3.5 | 4.65 | 3 | 3.2 | 2.65 | 2.35 | 4.35 | 3.59 |
| 2.3 |
| 2.8 |
| 3.29 |
| 2.5 |
| 4 | 5.6 | 3.9 | 4.3 | 3.5 | 3.2 | 5.3 | 4.44 | 3.05 | 3 | 4.14 | 3.25 |
| 4.5 | 7.15 | 4.2 | 5.8 | 4.85 | 4.55 | 6.85 | 5.89 | 4.35 | 3.5 | 5.59 | 4.6 |
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.
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