Standard: ISO 8746 - 2025
Available sizes: 2 to 6 (6 sizes)
| Standard Body | Standard Number |
|---|---|
| EN | EN 28746 |
| GB | GB /T 13829.8 |
| DIN | DIN EN ISO 8746 |
| ISO | ISO 8746 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | 2.5 |
| 2.65 |
| 2.7 |
| 1.6 |
| 1.4 |
| 2.425 |
| 4.6 |
| 1.5 |
| 2.4 |
| 4.2 |
| 0.75 |
| 2.5 | 4 | 4.2 | 4.25 | 2.55 | 2.25 | 3.9 | 7.25 | 1.5 | 3.8 | 6.75 | 1.2 |
| 3 | 6 | 6.225 | 6.3 | 3.75 | 3.45 | 5.9 | 10.8 | 1.5 | 5.6 | 10.2 | 1.8 |
| 4 | 10 | 10.25 | 10.35 | 7.4 | 6.5 | 9.85 | 16 | 2 | 8 | 14.9 | 3 |
| 5 | 16 | 16.3 | 16.4 | 10.9 | 10 | 15.8 | 26.1 | 3 | 13 | 23.7 | 4.8 |
| 6 | 20 | 20.375 | 20.5 | 13.9 | 13 | 19.8 | 33.1 | 3 | 16.5 | 30.7 | 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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