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 | 2 | 3.71 | 0.71 | 0.56 | 7.7 | 1.88 | 2.13 | 1.68 | 1.57 | 4.85 |
| 6# | 11.38 | 2 | 4.47 | 0.91 | 0.71 | 10.8 | 2.9 |
| 2.92 |
| 2.46 |
| 2.51 |
| 6.68 |
| 8# | 14.55 | 3 | 6.73 | 1.17 | 0.96 | 13.87 | 3.68 | 4.04 | 3.58 | 3.25 | 9.47 |
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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