Standard: GB 861.2 - 1987
Available sizes: 2 to 8 (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 2 | 2.7 | 0.3 | 7 | 2.95 | 5.2 | 5.5 | 0.04 |
| 2.5 | 4.3 | 0.5 | 8 | 4.6 | 7.64 | 8 | 0.12 |
| 3 | 6.4 | 0.6 | 9 | 6.76 | 10.57 | 11 | 0.26 |
| 4 |
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.
| 10.5 |
| 1 |
| 12 |
| 10.93 |
| 17.57 |
| 18 |
| 1.22 |
| 5 | 14.5 | 1.2 | 14 | 14.93 | 23.48 | 24 | 2.51 |
| 6 | 19 | 1.5 | 14 | 19.52 | 29.48 | 30 | 4.67 |
| 8 | 21 | 1.5 | 16 | 21.52 | 32.38 | 33 | 5.58 |
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