Standard: BS 1768 - 1963
Available sizes: (9/16) to 7/16 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (9/16) | 1.275 | 1.813 | 2.165 | 0.359 | 0.916 | 1.225 | 0.322 | 1.8750 | 1.8300 | 0.312 | 0.866 |
| 1/2 | 1.015 | 1.473 | 1.732 | 0.281 | 0.734 | 0.985 |
| 0.260 |
| 1.5000 |
| 1.4880 |
| 0.250 |
| 0.704 |
| 1/4 | 0.333 | 0.483 | 0.577 | 0.094 | 0.239 | 0.323 | 0.104 | 0.5000 | 0.4930 | 0.094 | 0.229 |
| 3/8 | 0.614 | 0.855 | 1.010 | 0.156 | 0.458 | 0.604 | 0.166 | 0.8750 | 0.8670 | 0.156 | 0.448 |
| 5/16 | 0.458 | 0.668 | 0.794 | 0.125 | 0.333 | 0.448 | 0.135 | 0.6875 | 0.6795 | 0.125 | 0.323 |
| 5/8 | 1.530 | 2.188 | 2.598 | 0.422 | 1.108 | 1.470 | 0.385 | 2.2500 | 2.2050 | 0.375 | 1.048 |
| 7/16 | 0.822 | 1.100 | 1.300 | 0.219 | 0.604 | 0.802 | 0.198 | 1.1250 | 1.1150 | 0.188 | 0.584 |
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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