Standard: GB /T 33943 - 2017
Available sizes: (M22) to M24 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| (M22) | 3 | 380.97~472.77 | 477.36~569.16 | 90 | 79 | 144 |
| (M27) | 4 | 810.08~1005.28 | 1015.04~1210.24 | 116 | 103 | 194 |
| M20 | 2.5 | 251.49~312.09 | 315.12~375.72 | 74 | 69 | 116 |
| M24 | 3.5 | 576.02~714.82 |
| 721.76~860.56 |
| 102 |
| 91 |
| 168 |
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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