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 | 0.9200 | 0.8451 | 1.0000 | 0.9920 | 3-1/2 | 4 | 0.9251 | 0.8360 |
| 1/4 | 18 | 5/16 | 0.2767 | 0.2442 | 0.3125 | 0.3073 | 1-1/8 | 1-1/4 | 0.2798 | 0.2383 |
| 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 |
| 0.5091 |
| 0.4595 |
| 0.5625 |
| 0.5560 |
| 2 |
| 2-1/4 |
| 0.5129 |
| 0.4521 |
| 5/16 | 14 | 7/16 | 0.3918 | 0.3495 | 0.4375 | 0.4316 | 1-5/8 | 1-3/4 | 0.3952 | 0.3428 |
| 5/8 | 6 | 1-1/2 | 1.3933 | 1.2924 | 1.5000 | 1.4906 | 5-1/4 | 6 | 1.3991 | 1.2818 |
| 7/16 | 10 | 3/4 | 0.6860 | 0.6263 | 0.7500 | 0.7428 | 2-5/8 | 3 | 0.6903 | 0.6182 |
| 9/16 | 7 | 1-1/4 | 1.1585 | 1.0725 | 1.2500 | 1.2413 | 4-1/2 | 5 | 1.1640 | 1.0627 |
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