Standard: BS 2470 - 1973
Available sizes: (3#) to 6# (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| (3#) | 0.2362 | 0.236 | 0.230 | 0.2297 | 0.375 | 0.113 | 1.000 | 0.365 | 3/16 |
| 4# | 0.2087 | 0.209 | 0.204 | 0.2027 | 0.312 | 0.100 | 1.000 | 0.303 | 5/32 |
| 5# |
| 0.1614 |
| 0.161 |
| 0.156 |
| 0.1559 |
| 0.250 |
| 0.075 |
| 0.875 |
| 0.242 |
| 1/8 |
| 6# | 0.1260 | 0.126 | 0.122 | 0.1212 | 0.219 | 0.058 | 0.750 | 0.211 | 3/32 |
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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