Standard: GB /T 1231
Available sizes: (M22) to M24 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M22) | 3.5 | 19.95 | 22.05 | 34 | 32 | 0.8 | 0.4 | 60.79 | 21 | 39.84 | 51.1 |
| M12 | 2 | 9.25 | 10.75 | 16.43 | 15.57 | 0.8 | 0.4 |
| 29.56 |
| 10 |
| 19.23 |
| 24.9 |
| M16 | 2.5 | 13.1 | 14.9 | 22.52 | 21.48 | 0.8 | 0.4 | 39.55 | 14 | 26.32 | 33.3 |
| M20 | 3 | 16.1 | 17.9 | 27.84 | 26.16 | 0.8 | 0.4 | 50.85 | 17 | 32.84 | 42.8 |
| M24 | 4 | 21.45 | 23.55 | 37 | 35 | 0.8 | 0.4 | 66.44 | 22.5 | 42.84 | 55.9 |
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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