Standard: JB /T 8547 - 2020
Available sizes: 25 to 42 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 25 | 1.3 | 1.45 | 1.55 | 2.495 | 2.47 | 1.4 | 1.2 | 0.3～0.5 | 1.6 | 2.5 | 3 |
| 28 | 1.7 | 1.45 | 1.55 | 2.495 | 2.47 | 1.8 | 1.6 | 0.3～0.5 |
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.
| 1.6 |
| 2.5 |
| 3 |
| 30 | 2 | 1.45 | 1.55 | 2.495 | 2.47 | 2.1 | 1.9 | 0.3～0.5 | 1.6 | 2.5 | 3 |
| 32 | 2.2 | 1.45 | 1.55 | 2.495 | 2.47 | 2.3 | 2.1 | 0.3～0.5 | 1.6 | 2.5 | 3 |
| 35 | 2.5 | 1.45 | 1.55 | 2.495 | 2.47 | 2.6 | 2.4 | 0.3～0.5 | 1.6 | 2.5 | 3 |
| 38 | 2.5 | 1.45 | 1.55 | 2.495 | 2.47 | 2.6 | 2.4 | 0.3～0.5 | 1.6 | 2.5 | 4 |
| 40 | 2.5 | 1.45 | 1.55 | 2.495 | 2.47 | 2.6 | 2.4 | 0.3～0.5 | 1.6 | 2.5 | 5 |
| 42 | 2.5 | 1.45 | 1.55 | 2.495 | 2.47 | 2.6 | 2.4 | 0.3～0.5 | 1.6 | 2.5 | 5 |
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