Standard: ZQ 4341 - 2006
Available sizes: 20 to 32 (8 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 20 | 1.5 | 1.85 | 23.29 | 2 | 1.44 | 23.5 | 2.8 | 12.1 | 23.92 | 4.7 |
| 22 | 1.5 | 2.16 | 26.69 | 2 | 1.44 | 26.9 | 3.1 | 14.5 | 27.32 | 5 |
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.
| 24 | 1.5 | 2.48 | 29.85 | 2 | 1.44 | 30.1 | 3.2 | 16.9 | 30.6 | 5.3 |
| 25 | 1.5 | 2.94 | 34.15 | 2 | 1.44 | 34.4 | 3.4 | 20 | 34.9 | 5.7 |
| 26 | 1.75 | 4.62 | 37.55 | 2.5 | 1.69 | 37.8 | 3.8 | 22.4 | 38.3 | 6 |
| 28 | 1.75 | 4.8 | 40.55 | 2.5 | 1.69 | 40.8 | 3.9 | 24.7 | 41.3 | 6.3 |
| 30 | 2 | 6.18 | 45.11 | 2.5 | 1.93 | 45.5 | 4.1 | 27.9 | 46.4 | 6.78 |
| 32 | 2 | 7 | 50.04 | 2.5 | 1.93 | 50.5 | 4.4 | 31.9 | 51.6 | 7.2 |
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