Standard: UNI 1751 - 1941
Available sizes: 2.2 to 4.8 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| DIN | DIN 127(B) |
| UNI | UNI 1751 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2.2 | 2.5 | 1.2 | 4.5 | 1.1 | 0.9 | 2.7 | 2.4 | 0.7 | 0.5 | 1 | 0.6 |
| 2.5 | 3.2 | 1.6 | 5.8 | 1.4 | 1.2 | 3.4 | 3.1 | 0.9 |
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.
| 0.7 |
| 1.3 |
| 0.8 |
| 2.8 | 4.3 | 1.8 | 7.3 | 1.6 | 1.4 | 4.5 | 4.2 | 1 | 0.8 | 1.5 | 0.9 |
| 3.2 | 5.3 | 2.4 | 8.9 | 1.9 | 1.7 | 5.5 | 5.2 | 1.3 | 1.1 | 1.8 | 1.2 |
| 3.7 | 6.7 | 3.2 | 11.7 | 2.65 | 2.35 | 6.9 | 6.6 | 1.7 | 1.5 | 2.5 | 1.6 |
| 4.3 | 8.4 | 4 | 14.4 | 3.15 | 2.85 | 8.6 | 8.3 | 2.1 | 1.9 | 3 | 2 |
| 4.8 | 9.5 | 4 | 15.5 | 3.15 | 2.85 | 9.8 | 9.3 | 2.1 | 1.9 | 3 | 2 |
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