Standard: BS 2693
Available sizes: 1/2 to 9/16 (7 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 10 | 1 | 0.9360 | 0.8771 | 1.0000 | 0.9924 | 3-1/2 | 4 | 0.9411 | 0.8686 |
| 1/4 | 22 | 5/16 | 0.2832 | 0.2572 | 0.3125 | 0.3077 | 1-1/8 | 1-1/4 | 0.2863 | 0.2517 |
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.
| 3/8 | 16 | 9/16 | 0.5225 | 0.4863 | 0.5625 | 0.5566 | 2 | 2-1/4 | 0.5263 | 0.4797 |
| 5/16 | 18 | 7/16 | 0.4019 | 0.3697 | 0.4375 | 0.4320 | 1-5/8 | 1-3/4 | 0.4053 | 0.3635 |
| 5/8 | 8 | 1-1/2 | 1.4200 | 1.3458 | 1.5000 | 1.4913 | 5-1/4 | 6 | 1.4258 | 1.3360 |
| 7/16 | 12 | 3/4 | 0.6966 | 0.6475 | 0.7500 | 0.7432 | 2-5/8 | 3 | 0.7009 | 0.6398 |
| 9/16 | 9 | 1-1/4 | 1.1789 | 1.1133 | 1.2500 | 1.2419 | 4-1/2 | 5 | 1.1844 | 1.1042 |
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