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 | 0.047 | 0.195 | 1.98 | 1.57 | 4.95 | 1.19 | 1 | 0.225 | 0.96 | 2.77 |
| 4# | 8.43 | 0.07 | 0.292 | 2.72 | 2.26 | 7.42 | 1.78 |
| 2 |
| 0.332 |
| 1.47 |
| 4.22 |
| 6# | 11.13 | 0.092 | 0.389 | 3.07 | 2.62 | 9.88 | 2.34 | 3 | 0.438 | 1.98 | 5.72 |
| 8# | 16.13 | 0.134 | 0.568 | 4.37 | 3.91 | 14.43 | 3.4 | 4 | 0.635 | 2.95 | 7.85 |
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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