Standard: GB /T 1228 - 1991
Available sizes: (M22) to M20 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| (M22) | 3.5 | 19.75 | 17.65 | 30.84 | 29.16 | 49 | 18.7 | 50 |
| M12 | 2 | 10.75 | 9.25 | 16.43 | 15.57 | 26.16 | 10 | 27 |
| M16 | 2.5 | 14.9 | 13.1 | 22.52 |
| 21.48 |
| 35 |
| 14 |
| 36 |
| M20 | 3 | 17.9 | 16.1 | 27.84 | 26.16 | 45 | 17 | 46 |
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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