Standard: ASME B 18.16
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 | 1.0000 | 1.418 | 1.427 | 1.619 | 8 | 12 | 1.016 | 0.825 | 1.440 | 1.078 |
| 1/4 | 0.3125 | 0.475 | 0.489 | 0.557 | 18 | 24 | 0.329 | 0.25 | 0.502 | 0.359 |
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.
| 3/8 | 0.5625 | 0.830 | 0.861 | 0.982 | 12 | 18 | 0.626 | 0.469 | 0.877 | 0.656 |
| 5/16 | 0.4375 | 0.597 | 0.616 | 0.698 | 14 | 20 | 0.438 | 0.324 | 0.627 | 0.468 |
| 5/8 | 1.5000 | 2.148 | 2.159 | 2.473 | 6 | 12 | 1.578 | 1.313 | 2.197 | 1.640 |
| 7/16 | 0.7500 | 1.033 | 1.052 | 1.191 | 10 | 16 | 0.860 | 0.742 | 1.064 | 0.890 |
| 9/16 | 1.2500 | 1.793 | 1.801 | 2.046 | 7 | 12 | 1.360 | 1.125 | 1.815 | 1.422 |
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