Standard: QC /T 379 - 2013
Available sizes: 1/2 to 3/8 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 1/2 | 27 | 15 | 36 | 26.67 | 21 | 1° | 37 | 3° |
| 1/4 | 16 | 10 | 14 | 15.73 | 14 | 1° | 23 | 3° |
| 1/8 | 8 | — | — | 7.78 | 11 | 1° | 18 | 3° |
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.
| 3/4 |
| 34 |
| 16 |
| 45 |
| 33.38 |
| 21 |
| 1° |
| 39 |
| 3° |
| 3/8 | 21 | 14 | 22 | 20.67 | 19 | 1° | 31 | 3° |
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