Standard: GB /T 8 - 2021
Available sizes: (M14) to M20 (7 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| (M14) | 2.5 | 6.3 | 12.10 | 8.47 | 37.91 | 13 | 30 | 29.16 | 13.90 | 0.8 |
| (M18) | 3.5 | 8.8 | 17.95 | 12.56 | 58.5 | 19 | 46 | 45 | 20.05 | 1 |
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.
| (M22) | 5 | 12.5 | 28.95 | 20.26 | 95.03 | 30 | 75 | 73.1 | 31.05 | 1.6 |
| M10 | 1.75 | 4.2 | 7.55 | 5.91 | 22.84 | 8 | 18 | 17.57 | 8.45 | 0.6 |
| M12 | 2.0 | 5 | 9.25 | 6.47 | 30.11 | 10 | 24 | 23.16 | 10.75 | 0.6 |
| M16 | 3 | 7.5 | 14.10 | 9.87 | 45.5 | 15 | 36 | 35 | 15.90 | 0.8 |
| M20 | 4.5 | 11.3 | 24.95 | 17.46 | 82.03 | 26 | 65 | 63.1 | 27.05 | 1.2 |
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