Standard: JB /T 7590 - 2005
Available sizes: D16 to D35 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| D16 | 18.6 | 15.1 | 14.3 | 19 | 18.2 | 0.3 | 3 | 14.7 | 2.7 |
| D19 | 25 | 19.1 | 18.3 | 25.4 | 24.6 | 0.3 | 3 | 18.7 | 4 |
| D22 | 29 | 23.2 |
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.
| 22 |
| 29.6 |
| 28.4 |
| 0.5 |
| 3 |
| 22.6 |
| 3.1 |
| D26 | 34 | 28.4 | 27.2 | 34.6 | 33.4 | 0.5 | 3 | 27.8 | 4.3 |
| D28 | 40.6 | 34.7 | 33.5 | 41.2 | 40 | 0.5 | 4 | 34.1 | 3.3 |
| D30 | 50.5 | 41.6 | 40.4 | 51.1 | 49.9 | 0.5 | 5 | 41 | 3.2 |
| D32 | 69.1 | 59.9 | 58.3 | 69.9 | 68.3 | 0.5 | 5 | 59.1 | 5.5 |
| D35 | 83.1 | 73.9 | 72.3 | 83.9 | 82.3 | 0.6 | 6 | 73.1 | 4 |
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