Standard: BS 450 - 1958
Available sizes: 1/4 to 5/16 (4 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 0.4375 | 0.227 | 0.729 | 0.197 | 14 | 18 | 0.386 | 0.245 | 0.766 | 4 |
| 1/8 | 0.1875 | 0.088 | 0.307 | 0.084 | 24 | 32 | 0.166 | 0.106 | 0.328 |
| 2 |
| 3/16 | 0.3125 | 0.150 | 0.518 | 0.141 | 18 | 22 | 0.309 | 0.168 | 0.547 | 4 |
| 5/16 | 0.5000 | 0.258 | 0.835 | 0.225 | 12 | 16 | 0.417 | 0.276 | 0.875 | 4 |
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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