Standard: QC /T 378 - 2013
Available sizes: 1/2 to 3/8 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 1/2 | 19 | 20 | 16 | 19.275 | 19.065 | 21.73 |
| 1/4 | 12 | 14 | 9 | 12.142 | 12.032 | 13.72 |
| 1/8 | 6 | 11 | 6 | 6.095 | 6.02 | 6.84 |
| 3/8 | 19 | 19 | 13 | 19.275 |
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.
| 19.065 |
| 21.73 |
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