Standard: BS 3575 - 1963
Available sizes: 1/8 to 9/64 (5 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 1/8 | 0.156 | 3/16 | 0.307 | 0.040 | 0.151 | 5/16 | 3/16 ② | 0.106 | 0.317 | 0.035 |
| 11/64 | 0.375 | 1/2 | 0.610 | 0.080 | 0.370 | 5/8 | 9/32 | 0.281 | 0.625 |
| 0.070 |
| 3/32 | 0.125 | 3/16 | 0.208 | 0.030 | 0.120 | 7/32 | 5/32 ① | 0.082 | 0.218 | 0.025 |
| 5/32 | 0.250 | 3/8 | 0.468 | 0.060 | 0.245 | 15/32 | 7/32 | 0.180 | 0.478 | 0.050 |
| 9/64 | 0.188 | 1/4 | 0.354 | 0.045 | 0.183 | 3/8 | 7/32 ③ | 0.136 | 0.364 | 0.040 |
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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