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# | 5.56 | 0.205 | 0.219 | 4.4 | 2.11 | 5.21 | 1.73 | 2.90 | 1 | 1.47 | 1.7 |
| 4# | 8.18 | 0.306 | 0.322 | 6.2 | 2.74 | 7.77 | 2.44 |
| 4.29 |
| 2 |
| 2.16 |
| 2.28 |
| 6# | 10.8 | 0.407 | 0.425 | 8.2 | 3.53 | 10.34 | 3.18 | 6.25 | 3 | 2.84 | 3.07 |
| 8# | 15.62 | 0.594 | 0.615 | 13.4 | 4.85 | 15.09 | 4.52 | 8.46 | 4 | 4.11 | 4.39 |
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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