Standard: ZQ 4342 - 2006
Available sizes: 15 to 25 (8 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 15 | 1.5 | 1.19 | 14.34 | 2 | 1.44 | 14.7 | 5 | 26.5 | 14.8 | 2.5 |
| 16 | 1.5 | 1.56 | 16.14 | 2 | 1.44 | 16.5 | 5.1 | 28.7 | 16.6 | 2.7 |
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.
| 17 | 1.75 | 2.42 | 20.08 | 2 | 1.69 | 20.5 | 6 | 34.6 | 20.63 | 3.1 |
| 18 | 1.75 | 3.59 | 22.78 | 2 | 1.69 | 23.2 | 6.4 | 38.5 | 23.41 | 3.4 |
| 20 | 2 | 5.35 | 27.48 | 2 | 1.93 | 27.9 | 6.5 | 43.7 | 28.11 | 4.1 |
| 22 | 2 | 7.05 | 31 | 2.5 | 1.93 | 31.5 | 6.6 | 47.9 | 31.75 | 4.2 |
| 24 | 2.5 | 8.3 | 34.7 | 2.5 | 2.43 | 35.2 | 6.8 | 52.3 | 35.45 | 4.3 |
| 25 | 2.5 | 8.6 | 35.6 | 2.5 | 2.43 | 36.5 | 7 | 54.7 | 36.89 | 4.4 |
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