Standard: QJ 3142 - 2001
Available sizes: 2 to 3.5 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 2 | 2.5 | 5.32 | 0.9 | 2.6 | 5.2 | 0.1 | 5.08 | 0.2 |
| 2.5 | 3.5 | 7.05 | 1.1 | 3.6 | 6.9 | 0.1 | 6.75 | 0.2 |
| 3 | 5 | 9.65 | 1.4 | 5.1 | 9.5 | 0.3 | 9.35 | 0.4 |
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.
| 3.5 |
| 8 |
| 15.78 |
| 2.3 |
| 8.15 |
| 15.6 |
| 0.3 |
| 15.42 |
| 0.4 |
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