Standard: GB /T 16939 - 1997
Available sizes: M12 to M22 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M12 | 2 | 54 | 6.75 | 20.38 | 14.35 | 17 | 21 | 7.5 | 8.25 | 21 | 13.65 |
| M14 | 2.5 | 73 | 11.6 | 29.38 | 20.42 | 25 | 30 |
| 12.5 |
| 13.4 |
| 30 |
| 19.58 |
| M16 | 3 | 82 | 14.1 | 35.38 | 24.42 | 30 | 36 | 15 | 15.9 | 36 | 23.58 |
| M20 | 3.5 | 98 | 17.65 | 45.38 | 30.42 | 37 | 44 | 18.7 | 19.75 | 46 | 29.58 |
| M22 | 3.5 | 101 | 19.95 | 49.38 | 33.5 | 40 | 47 | 21 | 22.05 | 50 | 32.5 |
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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