Standard: QJ 2582 - 1993
Available sizes: M2 to M4 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M2 | 0.45 | 2.02 | 2 | 2.5 | 2.36 | 17 | 4.5 | 2.5 | 2.36 | 4.32 | 2.30 |
| M2.5 | 0.7 | 3.02 | 3 | 4 | 3.82 | 20 | 7 |
| 4 |
| 3.82 |
| 6.78 |
| 3.44 |
| M3 | 1 | 5.02 | 5 | 6 | 5.82 | 24 | 10 | 6 | 5.70 | 9.78 | 5.72 |
| M4 | 1.25 | 6.06 | 6 | 8 | 7.78 | 28 | 13 | 8 | 7.64 | 12.73 | 6.86 |
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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