Standard: UNI 5449 - 1971
Available sizes: M3 to M8 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| DIN | DIN 316 |
| UNI | UNI 5449 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M3 | 8 | 3.2 | 5.2 | 17.6 | 1.6 | 8.6 |
| M4 | 12.7 | 5.1 | 8.4 | 27.8 | 2.5 |
| 13.6 |
| M5 | 16.5 | 6.8 | 11 | 36.2 | 3.3 | 17.7 |
| M6 | 26.6 | 10.7 | 18 | 58.3 | 5.2 | 28.5 |
| M8 | 26.6 | 10.7 | 18 | 58.3 | 5.2 | 28.5 |
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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