Standard: BS 2470 - 1973
Available sizes: 1/4 to 5/16 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 0.3105 | 1/4 | 0.117 | 0.219 | 0.213 | 0.3085 | 0.438 | 0.418 | 5/32 | 0.419 | 0.438 |
| 3/8 | 0.7480 | 5/8 | 0.281 | 0.500 | 0.492 | 0.7460 | 1 |
| 0.845 |
| 3/8 |
| 0.977 |
| 0.875 |
| 5/16 | 0.4980 | 3/8 | 0.188 | 0.313 | 0.306 | 0.4960 | 0.750 | 0.595 | 1/4 | 0.729 | 0.625 |
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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