Standard: JB /T 9157 - 2011
Available sizes: 3.2 to 8 (6 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3.2 | 4.2 | 3 | 4.04 | 5.85 | 5.55 | 4.35 | 4.05 | 1.5 | 4 | 5.7 | 0.3 |
| 4 | 6.7 | 5 | 6.04 | 9.15 | 8.85 | 6.85 | 6.55 |
| 2.5 |
| 6 |
| 9 |
| 0.3 |
| 5 | 8.7 | 7 | 8.04 | 12.35 | 12.05 | 8.85 | 8.55 | 3.5 | 8 | 12.2 | 0.3 |
| 6 | 11.2 | 9 | 10.04 | 16 | 15.6 | 11.4 | 11 | 4.5 | 10 | 15.8 | 0.5 |
| 7 | 15.2 | 12.5 | 14.04 | 21.7 | 21.3 | 15.4 | 15 | 6.35 | 14 | 21.5 | 0.5 |
| 8 | 17.2 | 14.5 | 16.04 | 24 | 23.6 | 17.4 | 17 | 7.15 | 16 | 23.8 | 0.5 |
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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