Standard: GB /T 24425.3 - 2009
Available sizes: M3 to M7 (5 sizes)
| Size | P | r | k_max | k_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| M3 | 0.7 | 0.5 | 5.6 | 2.4 | 40° | 90° | 5.05 | 3.2 |
| M4 | 1 | 0.7 | 7.95 | 3.5 | 40° | 90° | 7.58 | 4.8 |
| M5 | 1.25 | 1 | 10.35 | 4.7 |
| 40° |
| 80° |
| 9.85 |
| 6.3 |
| M6 | 1.75 | 1.6 | 15 | 6.9 | 30° | 70° | 14.50 | 9.5 |
| M7 | 2 | 2 | 19.9 | 9.1 | 30° | 70° | 18.87 | 12.5 |
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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