Standard: ASME B 18.27
Available sizes: 1/4 to 9/32 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | NA6-50 | 0.065 | 0.075 | 0.035 | 0.037 | 0.441 | 0.447 | 0.581 | 0.070 | 0.435 | 0.033 |
| 1/8 | NA6-15 | 0.034 | 0.040 | 0.015 | 0.017 | 0.131 | 0.133 | 0.205 |
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.
| 0.037 |
| 0.127 |
| 0.013 |
| 15/64 | NA6-40 | 0.059 | 0.067 | 0.025 | 0.027 | 0.359 | 0.362 | 0.486 | 0.063 | 0.354 | 0.023 |
| 3/16 | NA6-25 | 0.046 | 0.054 | 0.025 | 0.027 | 0.211 | 0.214 | 0.311 | 0.050 | 0.206 | 0.023 |
| 5/32 | NA6-21 | 0.041 | 0.047 | 0.025 | 0.027 | 0.187 | 0.190 | 0.275 | 0.044 | 0.182 | 0.023 |
| 7/32 | NA6-31 | 0.049 | 0.057 | 0.025 | 0.027 | 0.270 | 0.273 | 0.376 | 0.053 | 0.265 | 0.023 |
| 9/32 | NA6-62 | 0.076 | 0.086 | 0.035 | 0.037 | 0.553 | 0.559 | 0.715 | 0.081 | 0.547 | 0.033 |
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