Standard: BS 1981 - 1991
Available sizes: (1#) to 6# (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (1#) | 0.199 | 0.027 | 0.047 | 0.171 | 0.042 | 0.035 | 0.038 |
| (3#) | 0.332 | 0.045 | 0.078 | 0.292 | 0.07 | 0.054 | 0.064 |
| 0# | 0.146 | 0.019 | 0.034 | 0.123 | 0.031 | 0.026 | 0.027 |
| 2# | 0.252 | 0.035 | 0.059 | 0.22 | 0.053 | 0.043 | 0.048 |
| 4# | 0.438 | 0.056 | 0.103 | 0.389 | 0.092 | 0.067 | 0.085 |
| 5# | 0.635 | 0.072 | 0.149 | 0.568 | 0.134 | 0.084 | 0.124 |
| 6# | 0.762 | 0.081 | 0.179 | 0.685 | 0.161 | 0.094 | 0.149 |
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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