Standard: ANSI B 18.13
Available sizes: ST2.9 to ST4.8 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ST2.9 | 1.3 | 1.06 | 1.90 | 6.43 | 6.09 | 3.08 | 2.95 | 6.60 | 2.10 | 0.86 | 7.00 |
| ST3.5 | 1.6 | 1.26 | 2.70 | 8.43 | 8.07 | 4.11 | 3.96 |
| 9.10 |
| 3.00 |
| 1.42 |
| 9.50 |
| ST4.2 | 1.8 | 1.66 | 3.30 | 11.82 | 11.41 | 5.52 | 5.31 | 11.60 | 3.60 | 1.57 | 12.00 |
| ST4.8 | 2.1 | 2.56 | 5.70 | 15.95 | 15.54 | 8.59 | 8.38 | 19.50 | 6.00 | 2.39 | 20.00 |
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.
© 2026 Ningbo Ruixi Metal Surface Technology Co., Ltd.. All rights reserved.