Standard: GB 7245 - 1987
Available sizes: (14) to 8 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (14) | 30.5 | 50.14 | 9.3 | 6 | 5.8 | 31.5 | 9.5 | 9 | 8.7 | 10.5 | 6.2 |
| 10 | 22.5 | 18.07 | 6.2 | 4.5 | 4.3 | 23.34 | 5.1 | 6 |
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.
| 5.8 |
| 5.9 |
| 4.7 |
| 12 | 27.5 | 36.69 | 8.3 | 5.5 | 5.3 | 28.5 | 6.5 | 8 | 7.7 | 7.5 | 5.7 |
| 3 | 4.1 | 0.12 | 1.3 | 0.8 | 0.7 | 4.4 | 1.2 | 1.2 | 1.1 | 1.4 | 0.9 |
| 4 | 6.1 | 0.495 | 2.1 | 1.3 | 1.2 | 6.68 | 2 | 2 | 1.9 | 2.2 | 1.4 |
| 5 | 10.2 | 1.86 | 3.15 | 2 | 1.9 | 10.9 | 2.85 | 3 | 2.85 | 3.15 | 2.1 |
| 6 | 14.2 | 5.12 | 4.2 | 3 | 2.85 | 14.9 | 3.9 | 4 | 3.8 | 4.3 | 3.15 |
| 8 | 18.2 | 9.82 | 5.2 | 3.6 | 3.4 | 19.04 | 4.5 | 5 | 4.8 | 5.1 | 3.8 |
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