Standard: GB /T 2878.4
Available sizes: M10 to M8 (7 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| M10 | 1.5 | 6 | 11 | 3 | 18.8 | 19 | 5 | 16 | 18.6 | 7.5 |
| M12 | 1.5 | 8 | 14 | 3 | 23.8 | 24 | 5 | 19 | 23.6 |
| 8.5 |
| M14 | 1.5 | 10 | 15 | 3 | 26.8 | 27 | 5 | 20 | 26.6 | 8.5 |
| M16 | 2 | 14 | 18.5 | 3 | 35.8 | 36 | 6 | 24.5 | 35.6 | 11 |
| M18 | 2 | 17 | 19 | 3 | 49.8 | 50 | 6 | 25.0 | 49.6 | 11 |
| M20 | 2 | 19 | 24 | 3 | 64.8 | 65 | 6 | 30.0 | 64.6 | 12 |
| M8 | 1 | 5 | 9.5 | 3 | 13.8 | 14 | 4 | 13.5 | 13.6 | 5.5 |
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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