Standard: UNI 5731 - 1965
Available sizes: M5 to M8 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M5 | 1 | 3 | 13 | 18 | / | 6 | 6.24 | 16.05 | 14.95 | 5.76 | 15.5 |
| M6 | 1.5 | 5 | 20 | 26 | 32 | 10 | 10.29 |
| 25.65 |
| 24.35 |
| 9.71 |
| 25 |
| M8 | 2 | 7 | 28 | 34 | 40 | 14 | 14.35 | 35.8 | 34.2 | 13.65 | 35 |
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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