Standard: QJ 3079.4 - 1998
Available sizes: M3 to M5 (3 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| M3 | 7.5 | 5.45 | 4.5 | 7.28 | 5 | 0.48 | 4.88 | 0.7 |
| M4 | 10.5 | 7.66 | 6 | 10.23 | 7 | 1.1 | 6.85 | 1.1 |
| M5 | 18 | 14.38 | 10 | 17.73 |
| 13 |
| 6.54 |
| 12.73 |
| 1.5 |
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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