Standard: ZQ 4321 - 1997
Available sizes: 14 to 38 (6 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 14 | M6 | 26 | 108 | 35 | 10 | 24 | 22 | 1 |
| 18 | M10 | 38 | 143 | 44 | 14 | 88 | 28 | 1.5 |
| 22 | M12 | 52 | 192 | 55 | 20 | 171 | 32 | 2 |
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.
| 25 |
| M12 |
| 60 |
| 210 |
| 59 |
| 24 |
| 188 |
| 32 |
| 2 |
| 33 | M12 | 66 | 225 | 62 | 27 | 200 | 32 | 2 |
| 38 | M12 | 76 | 250 | 67 | 32 | 223 | 32 | 2 |
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