Standard: GB /T 3390.1 - 2013
Available sizes: 21 to 34 (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 21 | 22 | 17 | 55 | 9.98 | 33.3 | 569 | 40 | 85 |
| 22 | 27 | 21.6 | 60 | 12.35 | 39.6 | 665 | 40 | 85 |
| 24 | 32 | 26 | 60 | 14.11 |
| 45.8 |
| 888 |
| 45.8 |
| 85 |
| 27 | 36 | 28.8 | 67 | 15.85 | 50.8 | 1084 | 50.8 | 85 |
| 30 | 46 | 36 | 83 | 19.62 | 63.3 | 1569 | 63.3 | 100 |
| 32 | 55 | 43.2 | 95 | 23.42 | 74.6 | 1569 | 74.6 | 100 |
| 34 | 60 | 45.6 | 100 | 25.92 | 84.5 | 1569 | 84.5 | 100 |
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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