Standard: BS 4929
Available sizes: 1/4 to 8# (4 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/4 | 14 | 0.619 | 0.568 | 0.482 | 20 | 0.6875 | 0.794 | 0.688 | 0.6795 | 0.223 |
| 10# | 18 | 0.450 | 0.406 | 0.345 | 24 | 0.5 | 0.577 | 0.500 | 0.493 |
| 0.15 |
| 5/16 | 12 | 0.787 | 0.731 | 0.621 | 18 | 0.875 | 1.01 | 0.875 | 0.867 | 0.286 |
| 8# | 24 | 0.337 | 0.285 | 0.241 | 36 | 0.375 | 0.433 | 0.375 | 0.362 | 0.083 |
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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