Standard: ANSI B 18.21
Available sizes: 4# to 8# (3 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 4# | 0.15 | 0.028 | 0.023 | 0.141 | 0.69 | 0.67 |
| 6# | 0.204 | 0.04 | 0.032 | 0.195 | 0.76 | 0.74 |
| 8# | 0.231 | 0.04 | 0.032 | 0.221 | 0.76 | 0.725 |
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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