Standard: QJ 2381 - 1992
Available sizes: M3 to M5 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M3 | 2.8 | 6 | 1 | 6.5 | 6.32 | 2.66 | 8 | 1.51 | 1.26 | 7.78 | 1.2 |
| M4 | 4.5 | 10 | 1.4 | 10 | 9.64 | 4.32 | 11 | 1.91 |
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.
| 1.66 |
| 10.73 |
| 1.6 |
| M5 | 7 | 15 | 2.4 | 13.5 | 13.07 | 6.78 | 17 | 2.81 | 2.56 | 16.73 | 2.5 |
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