Standard: GB /T 822 - 1988
Available sizes: M2 to M4 (4 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 822 |
| DIN | DIN EN ISO 7048 |
| ISO | ISO 7048 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M2 | 0.45 | 1 | 1.1 | 4.2 | 3.9 | 0.9 | 25 | 1.56 | 0.2 | 3.1 | 1.7 |
| M2.5 | 0.7 | 2 | 1.75 | 7 | 6.64 | 1.4 | 38 | 2.36 |
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.
| 0.4 |
| 4.7 |
| 2.5 |
| M3 | 1 | 3 | 2.5 | 10 | 9.64 | 2 | 38 | 3.2 | 0.4 | 6.8 | 3.5 |
| M4 | 1.5 | 4 | 3.8 | 15 | 14.57 | 3 | 38 | 5.7 | 0.5 | 11.2 | 6 |
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