Standard: BS 1981 - 1991
Available sizes: (3#) to 8# (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (3#) | 0.252 | 0.15 | 0.073 | 0.22 | 0.075 | 2 | 0.055 |
| 2# | 0.199 | 0.109 | 0.067 | 0.171 | 0.059 | 1 | 0.057 |
| 4# | 0.332 | 0.183 | 0.107 | 0.292 | 0.1 | 2 | 0.089 |
| 5# | 0.438 | 0.261 | 0.133 | 0.389 | 0.132 | 3 | 0.115 |
| 6# | 0.635 | 0.373 | 0.205 | 0.568 | 0.191 | 4 | 0.187 |
| 8# | 0.762 | 0.398 | 0.231 | 0.685 | 0.23 | 4 | 0.213 |
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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