Standard: BS 1769 - 1951
Available sizes: 1 to 7/8 (6 sizes)
| Size | P | k_max | k_min | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 1 | 5 | 3.18 | 1.040 | 2.7500 | 1.009 | 0.929 | 2.6900 | 0.960 |
| 1-1/8 | 4-1/2 | 3.61 | 1.169 | 3.1250 | 1.138 | 1.050 | 3.0650 | 1.081 |
| 1/2 | 11 | 1.23 | 0.397 | 1.0625 | 0.381 |
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.
| 0.337 |
| 1.0375 |
| 0.353 |
| 3/4 | 7 | 2.09 | 0.655 | 1.8125 | 0.639 | 0.579 | 1.7825 | 0.595 |
| 5/8 | 9 | 1.66 | 0.526 | 1.4375 | 0.510 | 0.458 | 1.4075 | 0.474 |
| 7/8 | 6 | 2.53 | 0.846 | 2.1875 | 0.815 | 0.747 | 2.1425 | 0.778 |
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