Standard: GB 939 - 1988
Available sizes: 3 to 5 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 8 | 5.9 | 5.7 | 8.2 | 7.8 | 7.5 | 8 | 6.7 | 6.3 | 8 | 6.5 |
| 4 | 10 | 8 | 7.8 | 9.2 | 8.8 | 11 | 11.5 |
| 6.7 |
| 6.3 |
| 9 |
| 6.5 |
| 5 | 16 | 12.7 | 12.5 | 13.2 | 12.8 | 17 | 17.5 | 8.7 | 8.3 | 13 | 8.5 |
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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