Standard: ANSI B 18.21
Available sizes: 1/2 to 7/16 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 1/2 | 0.927 | 0.084 | 0.075 | 0.894 | 1.447 | 1.4 |
| 1/4 | 0.332 | 0.05 | 0.04 | 0.32 | 0.607 | 0.59 |
| 3/8 | 0.596 | 0.067 | 0.055 | 0.576 | 1.034 | 0.99 |
| 5/16 | 0.464 | 0.067 | 0.05 |
| 0.448 |
| 0.858 |
| 0.8 |
| 7/16 | 0.795 | 0.084 | 0.07 | 0.768 | 1.265 | 1.24 |
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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