Standard: JB /T 14724
Available sizes: (M3.5) to M4 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 0.8 | 2.4 | 1.3 | 3.95 | 3.3 | 8.5 | 8.28 | 1.51 | 1.26 | 4.05 | 3.12 |
| M3 | 0.6 | 1.92 | 1 | 2.7 | 2.4 | 6 | 5.82 | 1.2 |
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.
| 1.06 |
| 2.8 |
| 2.26 |
| M4 | 1 | 3 | 1.6 | 4.9 | 3.9 | 10 | 9.78 | 1.91 | 1.66 | 5 | 3.6 |
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