Standard: BS 1769 - 1951
Available sizes: 1 to 7/8 (6 sizes)
| Size | P | k_max | k_min | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 1 | 5 | 3.18 | 1.759 | 2.7500 | 7/16 | 1/2 | 2.6900 | 1.679 |
| 1-1/8 | 4-1/2 | 3.61 | 2.013 | 3.1250 | 7/16 | 9/16 | 3.0650 | 1.925 |
| 1/2 | 11 | 1.23 | 0.631 |
| 1.0625 |
| 3/16 |
| 7/32 |
| 1.0375 |
| 0.587 |
| 3/4 | 7 | 2.09 | 1.139 | 1.8125 | 1/4 | 11/32 | 1.7825 | 1.079 |
| 5/8 | 9 | 1.66 | 0.885 | 1.4375 | 3/16 | 1/4 | 1.4075 | 0.833 |
| 7/8 | 6 | 2.53 | 1.378 | 2.1875 | 5/16 | 3/8 | 2.1425 | 1.310 |
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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