Standard: ASME B 18.21
Available sizes: 1/2 to 5/8 (3 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 0.7500 | 0.234 | 30° | 35° | 0.760 | 0.791 | 0.302 | 0.220 | 1.415 | 0.785 |
| 3/8 | 0.5000 | 0.156 | 30° | 35° | 0.510 | 0.535 | 0.243 | 0.145 | 1.035 |
| 0.530 |
| 5/8 | 1.0000 | 0.250 | 30° | 35° | 1.010 | 1.040 | 0.437 | 0.229 | 1.928 | 0.860 |
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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