Standard: BS 4174 - 1972
Available sizes: 4# to 8# (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 4# | 8.15 | 0.086 | 0.303 | 5.36 | 1.22 | 7.7 | 2.18 | 1.12 | 0.321 | 1.88 | 1 |
| 6# | 11.38 | 0.118 | 0.425 | 7.2 | 1.52 | 10.8 | 3 |
| 1.55 |
| 0.448 |
| 2.62 |
| 1.27 |
| 8# | 14.55 | 0.150 | 0.546 | 9.52 | 1.9 | 13.87 | 3.81 | 2 | 0.573 | 3.38 | 1.62 |
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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