Standard: GB 9074.26 - 1988
Available sizes: 2.5 to 5 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2.5 | 2.83 | 5.23 | 2 | 0.7 | 1.2 | 2.69 | 0.8 | 1.1 | 1.6 | 0.9 | 1.3 |
| 3 | 4.75 | 8.75 | 3.25 | 1.2 | 2.0 | 4.45 | 1.3 | 1.9 |
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.
| 2.6 |
| 1.4 |
| 2.1 |
| 4 | 7.64 | 13.64 | 5 | 1.9 | 3.0 | 7.28 | 2.0 | 2.85 | 4 | 2.1 | 3.15 |
| 5 | 11.53 | 19.53 | 7.5 | 2.85 | 4.0 | 11.1 | 3.0 | 3.8 | 6 | 3.15 | 4.2 |
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