Standard: GB 824 - 1976
Available sizes: 4 to 8 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 4 | 8.5 | 1 | 4.16 | 5 | 5.16 | 8.3 | 3.4 | 4 | 4.03 | 3 | 5.03 |
| 5 | 12.5 | 2 | 6.16 | 8 | 8.2 | 12.26 | 5.48 | 6 |
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.
| 6.03 |
| 5 |
| 8.04 |
| 6 | 18 | 2.5 | 7.70 | 10 | 10.2 | 17.76 | 7.58 | 7.5 | 7.54 | 7 | 10.04 |
| 8 | 24 | 3.5 | 10.74 | 14 | 14.24 | 23.72 | 11.7 | 10.5 | 10.55 | 11 | 14.05 |
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