Standard: GB /T 2671.1 - 2017
Available sizes: (M3.5) to M4 (5 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 2671.1 |
| DIN | DIN EN ISO 14580 |
| ISO | ISO 14580 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M3.5) | 1.25 | T45 | 3.20 |
| 9.2 |
| 5.8 |
| 2.5 |
| 13 |
| 0.40 |
| 2.0 |
| 12.73 |
| 5.5 |
| M2 | 0.45 | T8 | 1.10 | 3.1 | 1.85 | 0.9 | 4.5 | 0.10 | 0.7 | 4.32 | 1.71 |
| M2.5 | 0.6 | T15 | 1.50 | 4.1 | 2.6 | 1.2 | 6 | 0.10 | 1.0 | 5.82 | 2.46 |
| M3 | 0.8 | T25 | 2.00 | 5.7 | 3.65 | 1.6 | 8.5 | 0.20 | 1.3 | 8.28 | 3.47 |
| M4 | 1.5 | T50 | 3.80 | 11.2 | 6.9 | 3 | 16 | 0.40 | 2.4 | 15.73 | 6.54 |
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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