Standard: QC /T 879 - 2011
Available sizes: 01 to 04 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 01 | NST4.5 | 2.5 | 12.2 | 2.8~3.3 | 3.0~3.2 | 2.6 |
| 02 | NST4.5 | 6.5 | 15.2 | 2.8~3.3 | 3.0~3.2 | 6 |
| 03 | NST5 | 2.5 | 12.2 | 3.1~3.7 | 3.5~3.6 | 2.6 |
| 04 | NST5 | 6.5 | 15.2 | 3.1~3.7 |
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.
| 3.5~3.6 |
| 6 |
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