Standard: QC /T 624
Available sizes: 12 to 30 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 12 | 16.0~16.4 | 1.0 | 0.5 | 12.0 | 2.0 | 23.0 | 17.7~18.3 | 2.0 | 3.0 | 14.0 | 4.0 |
| 16 | 25.0~25.4 | 1.0 | 0.5 | 20.0 | 2.5 | 34.0 | 27.7~28.3 | 2.5 | 3.5 | 23.0 | 4.0 |
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.
| 20 | 35.0~35.5 | 1.0 | 0.7 | 29.0 | 3.0 | 45.0 | 37.6~38.4 | 3.0 | 4.0 | 32.0 | 5.0 |
| 25 | 45.0~45.6 | 1.0 | 1.0 | 38.0 | 3.0 | 56.0 | 49.5~50.5 | 3.5 | 4.5 | 42.0 | 6.0 |
| 30 | 55.0~55.7 | 1.0 | 1.0 | 46.0 | 3.0 | 68.0 | 59.5~60.5 | 4.0 | 5.0 | 52.0 | 6.0 |
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