Standard: GB /T 879.3 - 2018
Available sizes: Φ1.5 to Φ5 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| EN | EN 28748 |
| GB | GB /T 879.3 |
| DIN | DIN EN ISO 8748 |
| ISO | ISO 8748 |
| ANSI | ANSI/ASME B 18.8.3M(H) |
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| Φ1.5 | 2.21 | 0.22 | 3.5 | 2.11 | 1.9 | 0.7 | 2.5 |
| Φ2 | 3.25 | 0.33 | 7.6 | 3.12 | 2.9 | 0.9 | 5.7 |
| Φ2.5 | 4.3 | 0.45 | 13.5 | 4.15 | 3.9 | 1.1 | 10 |
| Φ3 |
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.
| 6.4 |
| 0.67 |
| 30 |
| 6.18 |
| 5.85 |
| 1.5 |
| 23 |
| Φ3.5 | 10.65 | 1.1 | 84 | 10.3 | 9.75 | 2.5 | 64 |
| Φ4 | 14.85 | 1.6 | 165 | 14.4 | 13.6 | 3.5 | — |
| Φ5 | 21 | 2.2 | 340 | 20.4 | 19.6 | 4.5 | — |
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.