Standard: ZQ 4446 - 1997
Available sizes: R1/4 to R3/8 (3 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| R1/4 | 21.42 | 0.03 | 9 | 7 | 12 | 10 | 10 | 11.5 | 8.2 | 15 |
| R1/8 | 13.406 | 0.006 | 6 | 4 | 7.5 | 6 | 5.5 | 5.7 | 6 | 10 |
| R3/8 | 33.81 | 0.102 |
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.
| 12 |
| 10 |
| 17 |
| 14 |
| 16 |
| 18.5 |
| 10.4 |
| 20 |
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