Standard: BS 4174 - 1972
Available sizes: 2# to 8# (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2# | 5.71 | 0.089 | 0.067 | 1.85 | 3.05 | 4.95 | 1.7 | 0.225 | 0.195 | 2.26 | 1 |
| 4# | 8.43 | 0.121 | 0.100 | 2.62 | 4.6 | 7.42 | 2.54 |
| 0.332 |
| 0.292 |
| 3.07 |
| 2 |
| 6# | 11.13 | 0.146 | 0.132 | 3.25 | 6.35 | 9.88 | 3.35 | 0.438 | 0.389 | 3.71 | 3 |
| 8# | 16.13 | 0.220 | 0.191 | 5.13 | 9.07 | 14.43 | 4.85 | 0.635 | 0.568 | 5.59 | 4 |
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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