Standard: ANSI B 18.6
Available sizes: ST2.2 to ST4.8 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ST2.2 | 1 | AB,B,BF,BT | 17 | 6.4 | 5.9 | 4 | 3.84 | 0.4 | 0.1 | 4.27 | 3.2 |
| ST2.9 | 1.4 | AB,B,BF,BT | 25 | 8.5 | 7.8 | 5.5 | 5.32 |
| 0.6 |
| 0.2 |
| 5.92 |
| 4.3 |
| ST3.5 | 1.8 | AB,B,BF,BT | 33 | 11.2 | 10.3 | 7 | 6.78 | 0.8 | 0.2 | 7.55 | 6 |
| ST4.2 | 2.1 | AB,B,BF,BT | 38 | 16.8 | 15.5 | 10 | 9.78 | 1.2 | 0.4 | 10.89 | 8.6 |
| ST4.8 | 2.1 | AB,B,BF,BT | 38 | 21 | 19.3 | 13 | 12.72 | 1.4 | 0.4 | 14.16 | 10.7 |
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.