Standard: ANSI B 18.21
Available sizes: 1/4 to 8# (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 1/4 | 0.766 | 0.154 | 0.108 | 0.753 | 1.105 | 0.218 |
| 10# | 0.512 | 0.103 | 0.072 | 0.502 | 0.733 | 0.172 |
| 4# | 0.133 | 0.030 | 0.021 | 0.127 | 0.202 | 0.030 |
| 5# | 0.174 | 0.042 | 0.029 |
| 0.167 |
| 0.267 |
| 0.047 |
| 6# | 0.260 | 0.047 | 0.033 | 0.252 | 0.363 | 0.078 |
| 8# | 0.385 | 0.076 | 0.053 | 0.377 | 0.550 | 0.125 |
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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