Standard: BS 4174 - 1972
Available sizes: 1/2 to 8# (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 4.24 | 0.053 | 0.155 | 0.79 | 0.58 | 3.94 | 1.35 | 0.89 | 0.167 | 1.14 | 0.68 |
| 2# | 6.86 | 0.082 | 0.256 | 1.22 | 0.99 | 6.5 | 2.08 |
| 1.17 |
| 0.270 |
| 1.83 |
| 1.12 |
| 4# | 9.47 | 0.110 | 0.357 | 1.52 | 1.27 | 9.07 | 2.79 | 1.55 | 0.373 | 2.51 | 1.55 |
| 6# | 12.5 | 0.144 | 0.473 | 1.9 | 1.63 | 12.01 | 3.66 | 2.21 | 0.492 | 3.3 | 2.01 |
| 8# | 15.62 | 0.178 | 0.594 | 2.13 | 1.83 | 15.09 | 4.52 | 2.51 | 0.615 | 4.11 | 2.44 |
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.