Standard: ASME B 18.3
Available sizes: 1/4 to 8# (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 0.875 | 0.265 | 0.619 | 0.875 | 0.8647 | 9 | 14 | 1.604 | 0.468 | 20 | 1.688 |
| 10# | 0.625 | 0.135 | 0.446 | 0.625 | 0.6163 | 11 | 18 |
| 1.112 |
| 0.324 |
| 24 |
| 1.188 |
| 2# | 0.112 | 0.035 | 0.111 | 0.112 | 0.1075 | 40 | 48 | 0.218 | 0.083 | — | 0.255 |
| 4# | 0.138 | 0.04 | 0.132 | 0.138 | 0.1329 | 32 | 40 | 0.263 | 0.097 | — | 0.307 |
| 5# | 0.19 | 0.05 | 0.178 | 0.19 | 0.184 | 24 | 32 | 0.359 | 0.127 | — | 0.411 |
| 5/16 | 1 | 0.285 | 0.795 | 1 | 0.9886 | 8 | 12 | 1.841 | 0.54 | 20 | 1.938 |
| 6# | 0.3125 | 0.087 | 0.266 | 0.3125 | 0.3053 | 18 | 24 | 0.6 | 0.198 | 32 | 0.656 |
| 8# | 0.4375 | 0.100 | 0.352 | 0.4375 | 0.4294 | 14 | 20 | 0.781 | 0.234 | 28 | 0.844 |
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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