Standard: BS 916 - 1953
Available sizes: 1/2 to 9/16 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 8 | 1.71 | 0.630 | 10 | 1.480 | 0.583 | 0.573 | 1.450 | 0.583 |
| 1/4 | 18 | 0.61 | 0.210 | 22 | 0.525 | / | / | 0.515 | 0.200 |
| 3/4 |
| 5 |
| 2.78 |
| 1.060 |
| 8 |
| 2.410 |
| 1.000 |
| 0.980 |
| 2.365 |
| 1.000 |
| 3/8 | 12 | 1.06 | 0.333 | 16 | 0.920 | / | / | 0.900 | 0.323 |
| 5/16 | 14 | 0.82 | 0.275 | 18 | 0.710 | / | / | 0.695 | 0.265 |
| 5/8 | 6 | 2.56 | 0.980 | 8 | 2.220 | 0.916 | 0.896 | 2.175 | 0.916 |
| 7/16 | 10 | 1.39 | 0.490 | 12 | 1.200 | 0.458 | 0.448 | 1.175 | 0.458 |
| 9/16 | 7 | 2.15 | 0.810 | 9 | 1.860 | 0.750 | 0.730 | 1.815 | 0.750 |
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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