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#) | 0.252 | 1 | 0.12 | 0.22 | 0.053 | 0.069 | 0.043 | 0.079 |
| 10# | 0.875 | 4 | 0.401 | 0.775 | 0.156 | 0.220 | 0.13 | 0.238 |
| 2# | 0.199 | 1 | 0.094 | 0.171 |
| 0.042 |
| 0.043 |
| 0.033 |
| 0.053 |
| 4# | 0.332 | 2 | 0.166 | 0.292 | 0.07 | 0.073 | 0.058 | 0.091 |
| 5# | 0.438 | 3 | 0.225 | 0.389 | 0.092 | 0.082 | 0.078 | 0.1 |
| 6# | 0.635 | 4 | 0.309 | 0.568 | 0.134 | 0.127 | 0.116 | 0.145 |
| 8# | 0.812 | 4 | 0.385 | 0.723 | 0.156 | 0.204 | 0.133 | 0.222 |
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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