Standard: BS 1981 - 1991
Available sizes: (3#) to 8# (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| (3#) | 0.205 | 2 | 0.132 | 0.187 | 0.120 | 0.036 | 0.100 | 0.054 |
| 10# | 0.75 | 4 | 0.412 | 0.710 | 0.412 | 0.228 | 0.362 | 0.246 |
| 2# | 0.161 | 1 | 0.104 | 0.145 | 0.095 |
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.
| 0.052 |
| 0.077 |
| 0.062 |
| 4# | 0.27 | 2 | 0.169 | 0.250 | 0.156 | 0.074 | 0.133 | 0.092 |
| 5# | 0.357 | 3 | 0.246 | 0.334 | 0.205 | 0.099 | 0.178 | 0.117 |
| 6# | 0.518 | 3 | 0.314 | 0.490 | 0.295 | 0.165 | 0.262 | 0.183 |
| 8# | 0.625 | 4 | 0.391 | 0.589 | 0.368 | 0.206 | 0.321 | 0.224 |
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