Standard: BS 1981 - 1991
Available sizes: (1#) to 6# (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| (1#) | 48 | 0.066 | 0.057 | 56 | 0.187 | 0.18 |
| (3#) | 32 | 0.13 | 0.117 | 36 | 0.344 | 0.332 |
| 0# | 64 | 0.05 | 0.043 | 72 | 0.156 | 0.15 |
| 2# | 40 | 0.114 | 0.102 | 44 |
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.
| 0.312 |
| 0.302 |
| 4# | 24 | 0.161 | 0.148 | 28 | 0.437 | 0.423 |
| 5# | 18 | 0.225 | 0.208 | 24 | 0.562 | 0.545 |
| 6# | 16 | 0.257 | 0.239 | 24 | 0.625 | 0.607 |
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