Standard: GB /T 1229 - 1991
Available sizes: (M22) to M20 (4 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M22) | 3.5 | 0.4 | 0.8 | 55.37 | 30.7 | 32.4 | 30 | 23.3 | 20.4 | 46.5 | 29.1 |
| M12 | 2 | 0.4 | 0.8 | 29.56 | 17.1 | 17.3 | 16 |
| 13.1 |
| 11.5 |
| 24.9 |
| 16.4 |
| M16 | 2.5 | 0.4 | 0.8 | 39.55 | 23.6 | 23.8 | 22 | 17.8 | 15.6 | 33.3 | 22.3 |
| M20 | 3 | 0.4 | 0.8 | 50.85 | 27.6 | 29.1 | 27 | 21 | 18.4 | 42.8 | 26.3 |
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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