Standard: ASME B 18.27
Available sizes: 0.512 to 7/16 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0.512 | NA2-86 | 0.160 | 0.060 | 0.042 | 0.044 | 0.951 | 0.966 | 0.062 | 0.072 | 0.941 | 0.040 |
| 1/2 | NA2-77 | 0.151 | 0.060 | 0.042 | 0.044 | 0.859 | 0.869 | 0.062 |
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.
| 0.072 |
| 0.854 |
| 0.040 |
| 1/4 | NA2-31 | 0.069 | 0.029 | 0.015 | 0.017 | 0.346 | 0.356 | 0.031 | 0.041 | 0.341 | 0.013 |
| 29/64 | NA2-68 | 0.137 | 0.060 | 0.035 | 0.037 | 0.763 | 0.773 | 0.062 | 0.072 | 0.758 | 0.033 |
| 3/8 | NA2-50 | 0.117 | 0.045 | 0.035 | 0.037 | 0.548 | 0.558 | 0.047 | 0.057 | 0.543 | 0.033 |
| 5/16 | NA2-43 | 0.101 | 0.039 | 0.025 | 0.027 | 0.482 | 0.492 | 0.041 | 0.051 | 0.477 | 0.023 |
| 7/16 | NA2-56 | 0.137 | 0.045 | 0.035 | 0.037 | 0.620 | 0.630 | 0.047 | 0.057 | 0.615 | 0.033 |
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