Standard: GB /T 71 - 2018
Available sizes: (M3.5) to M3 (6 sizes)
| Standard Body | Standard Number |
|---|---|
| EN | EN 27434 |
| GB | GB 71 |
| DIN | DIN EN 27434 |
| ISO | ISO 7434 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (M3.5) | 1.75 | 2.31 | 2.8 | 3 | 2 | 2.06 | 3.6 |
| M1.2 | 0.35 | 0.45 | 0.56 | 0.16 | 0.25 | 0.31 | 0.74 |
| M1.6 | 0.45 | 0.6 | 0.72 | 0.25 | 0.4 | 0.46 | 0.95 |
| M2 |
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.
| 0.6 |
| 0.7 |
| 0.96 |
| 0.35 |
| 0.5 |
| 0.56 |
| 1.21 |
| M2.5 | 0.8 | 1 | 1.28 | 0.5 | 0.8 | 0.86 | 1.63 |
| M3 | 1.25 | 1.51 | 2 | 2 | 1.2 | 1.26 | 2.5 |
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