Standard: MS 51865 - 1970
Available sizes: 1/4 to 8# (6 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 13 | 0.5 | 0.736 | 0.866 | 20 | 3/4 | 0.81 | 0.38 | 0.75 | 0.84 |
| 10# | 16 | 0.38 | 0.551 | 0.65 | 24 | 9/16 | 0.62 | 0.28 | 0.5625 |
| 0.628 |
| 3/8 | 10 | 0.75 | 1.045 | 1.227 | 16 | 1-1/16 | 1.16 | 0.53 | 1.0625 | 0.191 |
| 5/16 | 11 | 0.62 | 0.922 | 1.083 | 18 | 15/16 | 1 | 0.47 | 0.9375 | 1.051 |
| 6# | 32 | 0.16 | 0.302 | 0.361 | 36 | 5/16 | 0.34 | 0.16 | 0.3125 | 0.344 |
| 8# | 20 | 0.25 | 0.428 | 0.505 | 28 | 7/16 | 0.47 | 0.22 | 0.4375 | 0.488 |
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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