Standard: ANSI B 18.13
Available sizes: ST2.9 to ST4.8 (4 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| ST2.9 | 1.3 | 2.30 | 5.66 | 5.33 | 3.08 | 2.95 | 5.32 | 2.60 | 0.79 | 5.50 |
| ST3.5 | 1.6 | 3.30 | 7.47 | 7.10 | 4.11 | 3.96 | 7.78 | 3.80 | 1.19 |
| 8.00 |
| ST4.2 | 1.8 | 4.10 | 11.26 | 10.85 | 5.52 | 5.31 | 9.78 | 4.70 | 1.57 | 10.00 |
| ST4.8 | 2.1 | 6.50 | 15.95 | 15.54 | 8.59 | 8.38 | 15.73 | 7.50 | 2.39 | 16.00 |
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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