Standard: GB /T 7244 - 1987
Available sizes: (Φ14) to Φ8 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (Φ14) | 24.5 | 40.54 | 17.75 | 7.4 | 7.5 | 25.5 | 7.1 | 7.8 | 14.2 | 6.8 | 7.2 |
| (Φ18) | 36.5 | 134.1 | 27 | 11.1 | 11 | 37.7 | 10.8 | 11.3 |
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.
| 21.6 |
| 10.5 |
| 10.7 |
| Φ10 | 16.2 | 13.01 | 12 | 5 | 5.3 | 16.9 | 4.8 | 5.5 | 9.6 | 4.6 | 5.1 |
| Φ12 | 20.2 | 24.29 | 15 | 6.2 | 6.4 | 21.04 | 6 | 6.7 | 12 | 5.8 | 6.1 |
| Φ16 | 30.5 | 79.2 | 22.5 | 9.3 | 9.3 | 31.5 | 9 | 9.6 | 18 | 8.7 | 9 |
| Φ6 | 8.1 | 2.07 | 6 | 2.55 | 3.2 | 8.68 | 2.4 | 3.4 | 4.8 | 2.25 | 3 |
| Φ8 | 12.2 | 5.92 | 8.75 | 3.7 | 4.3 | 12.9 | 3.5 | 4.5 | 7 | 3.3 | 4.1 |
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