Standard: QJ 3142 - 2001
Available sizes: 2.5 to 3 (2 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2.5 | 3 | 0.15 | 0.44 | 4.5 | 1.07 | 3.1 | 5.55 | 0.4 | 0.36 | 4.95 | 0.06 |
| 3 | 4 | 0.25 | 0.68 | 5.78 | 1.43 | 4.1 | 7.4 | 0.64 | 0.6 | 6.6 | 0.08 |
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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