Standard: ZQ 4349 - 1986
Available sizes: 40 to 90 (7 sizes)
| Size | P | e | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 40 | 20 | 40 | 7 | 0.06 | 5 | 5.5 | 16 | 4 | M6 |
| 45 | 25 | ＞45~50 | 7 | 0.125 | 6 | 6.5 | 16 | 5 | M6 |
| 50 | 30 | ＞60~70 |
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.
| 14 |
| 0.22 |
| 6 |
| 6.5 |
| — |
| 5 |
| — |
| 60 | 40 | ＞80~90 | 14 | 0.47 | 8 | 8.5 | 25 | 7 | M12 |
| 70 | 60 | ＞110~130 | 14 | 1.08 | 8 | 8.5 | 25 | 7 | M12 |
| 80 | 110 | ＞160~200 | 18 | 3.57 | 12 | 12.5 | 30 | 10.5 | M16 |
| 90 | 140 | ＞200~240 | 18 | 4.93 | 12 | 12.5 | 30 | 10.5 | M16 |
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