Standard: GB /T 70.4 - 2015
Available sizes: M3 to M6 (4 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 70.4 |
| DIN | DIN EN ISO 7380(-2) |
| ISO | ISO 7380-2 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M3 | 0.7 | 1.95 | 2.20 |
| 8.82 |
| 7.2 |
| 0.8 |
| 0.65 |
| 4 |
| 3.82 |
| 9.4 |
| 6.8 |
| M4 | 1 | 3.0 | 3.3 | 12.9 | 10 | 1.2 | 1 | 6 | 5.82 | 13.6 | 9.6 |
| M5 | 1.5 | 5.2 | 5.5 | 21.06 | 16.5 | 2 | 1.7 | 10 | 9.78 | 21.9 | 16.1 |
| M6 | 2 | 8.44 | 8.80 | 33 | 26 | 2.8 | 2.5 | 16 | 15.73 | 34 | 25.5 |
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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