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 | 12 | 1 | 0.9459 | 0.9029 | 1.0000 | 0.9886 | 3-1/2 | 4 | 0.9510 | 0.8925 |
| 1/4 | 24 | 5/16 | 0.2852 | 0.2643 | 0.3125 | 0.3053 | 1-1/8 | 1-1/4 | 0.2883 | 0.2586 |
| 3/8 | 18 |
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 |
| 0.5264 |
| 0.4981 |
| 0.5625 |
| 0.5538 |
| 2 |
| 2-1/4 |
| 0.5302 |
| 0.4907 |
| 5/16 | 20 | 7/16 | 0.4050 | 0.3796 | 0.4375 | 0.4294 | 1-5/8 | 1-3/4 | 0.4084 | 0.3729 |
| 5/8 | 12 | 1-1/2 | 1.4459 | 1.4036 | 1.5000 | 1.4886 | 5-1/4 | 6 | 1.4517 | 1.3928 |
| 7/16 | 16 | 3/4 | 0.7094 | 0.6776 | 0.7500 | 0.7406 | 2-5/8 | 3 | 0.7137 | 0.6693 |
| 9/16 | 12 | 1-1/4 | 1.1959 | 1.1533 | 1.2500 | 1.2386 | 4-1/2 | 5 | 1.2014 | 1.1427 |
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