Standard: JB /T 7604.1 - 1994
Available sizes: M3 to M8×1 (6 sizes)
| Size | P | e | r | k_max | k_min | s_max | ds_max | ds_min | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| M3 | 5.12 | 0.5 | 90 | 2.5 | 3.2 | 5.30 | 0.28 | 40 | 0.21 |
| M4 | 7.62 | 0.7 | 90 | 3.9 | 4.9 | 7.80 | 0.4 | 40 | 0.30 |
| M5 | 9.82 | 1 |
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.
| 80 |
| 5.9 |
| 6.9 |
| 10.09 |
| 0.4 |
| 40 |
| 0.30 |
| M6 | 12.07 | 1.2 | 80 | 7.9 | 8.9 | 12.29 | 0.4 | 40 | 0.30 |
| M8 | 14.51 | 1.2 | 70 | 9.3 | 10.6 | 14.78 | 0.5 | 30 | 0.38 |
| M8×1 | 16.97 | 1.4 | 70 | 10.8 | 12.3 | 17.24 | 0.6 | 30 | 0.45 |
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