Standard: BS 4174 - 1972
Available sizes: 10# to 8# (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 10# | 13 | 0.230 | 0.545 | 5.95 | 5.65 | 12.73 | 15 | 0.489 | 0.577 | 14.28 | 0.500 |
| 4# | 5.5 | 0.110 | 0.272 | 2.42 | 2.18 | 5.32 | 6.4 |
| 0.244 |
| 0.289 |
| 5.95 |
| 0.250 |
| 6# | 8 | 0.120 | 0.340 | 3.12 | 2.88 | 7.78 | 9.2 | 0.305 | 0.361 | 8.71 | 0.312 |
| 8# | 10 | 0.190 | 0.409 | 4.95 | 4.65 | 9.78 | 11.5 | 0.367 | 0.433 | 10.94 | 0.375 |
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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