Standard: GB 1340 - 1977
Available sizes: 4 to 6 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 4 | 7 | 7.8 | 13.85 | 3.5 | 15.75 | 7.2 | 6.8 | 14 | 14.15 | 3.7 | 15.5 |
| 5 | 10 | 11.1 | 20.3 | 4.5 | 21.3 | 10.24 | 9.76 |
| 20.5 |
| 20.7 |
| 4.7 |
| 21 |
| 6 | 12 | 13.3 | 24.3 | 5.2 | 23.8 | 12.24 | 11.76 | 24.5 | 24.7 | 5.4 | 23.5 |
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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