Standard: ZQ 4444 - 1997
Available sizes: G1/4A to M8 (8 sizes)
| Size | P | e | r | k_max | k_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| G1/4A | 1.5 | 11.8 | 12.2 | 22.48 | 15.7 | 9.2 | 12 | 23 | 15.5 |
| G3/8A | — | 15.8 | 16.2 | 31.38 | 23.9 | 13.7 | 16 | 32 | 23.7 |
| M10 | — | 11.8 | 12.2 | 18.48 | 11.2 |
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.
| 6.9 |
| 12 |
| 19 |
| 11 |
| M12 | 1.5 | 11.8 | 12.2 | 20.48 | 13.7 | 9.2 | 12 | 21 | 13.5 |
| M14 | — | 13.8 | 14.2 | 26.48 | 18.4 | 11.4 | 14 | 27 | 18.2 |
| M16 | 1.5 | 13.8 | 14.2 | 28.48 | 21.7 | 13.7 | 14 | 29 | 21.5 |
| M18 | 1.5 | 15.8 | 16.2 | 35.38 | 27.7 | 19.4 | 16 | 36 | 27.5 |
| M8 | 1 | 7.8 | 8.2 | 13.57 | 8.3 | 5.7 | 8 | 14 | 8.1 |
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