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 | 8 | 1 | 0.9188 | 0.8517 | 1.0000 | 0.9850 | 3-1/2 | 4 | 0.9239 | 0.8376 |
| 1/4 | 18 | 5/16 | 0.2762 | 0.2472 | 0.3125 | 0.3038 | 1-1/8 | 1-1/4 | 0.2793 | 0.2402 |
| 3/8 | 12 |
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.
| 9/16 |
| 0.5084 |
| 0.4641 |
| 0.5625 |
| 0.5511 |
| 2 |
| 2-1/4 |
| 0.5122 |
| 0.4542 |
| 5/16 | 14 | 7/16 | 0.3911 | 0.3533 | 0.4375 | 0.4272 | 1-5/8 | 1-3/4 | 0.3945 | 0.3447 |
| 5/8 | 6 | 1-1/2 | 1.3917 | 1.3013 | 1.5000 | 1.4818 | 5-1/4 | 6 | 1.3975 | 1.2832 |
| 7/16 | 10 | 3/4 | 0.6850 | 0.6316 | 0.7500 | 0.7371 | 2-5/8 | 3 | 0.6893 | 0.6200 |
| 9/16 | 7 | 1-1/4 | 1.1572 | 1.0802 | 1.2500 | 1.2336 | 4-1/2 | 5 | 1.1627 | 1.0644 |
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