Standard: SJ 2839 - 1987
Available sizes: ST3 to ST4.0 (2 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ST3 | 1.41 | 1.35 | 1.93 | 2.55 | 1.41 | 8.5 | 8 | 2 | 4 | 2.85 | 3.7 |
| ST4.0 | 1.59 | 2.14 | 2.73 | 3.25 | 1.59 | 10.6 | 10 |
| 2 |
| 4.8 |
| 3.55 |
| 4.3 |
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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