Standard: QC /T 333 - 1999
Available sizes: 3 to 5 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 4.2 | 1.8 | 1.5 | 14.0 | 0.5 | 4.5 | 6.4 | 2.5 | 1.9 | 17 | 2.2 |
| 4 | 6.2 | 2.1 | 1.8 | 18.6 | 0.7 | 6.56 | 8.7 | 2.8 |
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.
| 2.2 |
| 22 |
| 2.5 |
| 5 | 10.2 | 2.9 | 2.6 | 23.6 | 1.2 | 10.63 | 13.5 | 3.475 | 2.725 | 27 | 3.1 |
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