Standard: ANSI B 18.5
Available sizes: 1/4 to 7/16 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 0.3125 | 0.124 | 0.307 | 0.719 | 0.688 | 18 | 0.324 | 0.156 | 0.324 | 0.272 | 0.176 |
| 3/8 | 0.6250 | 0.218 | 0.616 | 1.344 | 1.219 | 11 | 0.642 |
| 0.313 |
| 0.642 |
| 0.559 |
| 0.344 |
| 5/16 | 0.4375 | 0.156 | 0.431 | 0.969 | 0.907 | 14 | 0.452 | 0.219 | 0.452 | 0.385 | 0.239 |
| 7/16 | 0.7500 | 0.218 | 0.741 | 1.594 | 1.469 | 10 | 0.768 | 0.375 | 0.768 | 0.678 | 0.406 |
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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