Standard: ZQ 4755 - 2006
Available sizes: 25 to 74 (8 sizes)
| Size | P | k_max | s_max | s_min | k_nominal |
|---|---|---|---|---|---|
| 25 | 60 | M30 | 90 | 15 | 0.55 |
| 31 | 80 | M42 | 115 | 25 | 1.49 |
| 37 | 100 | M56 | 145 | 30 | 2.83 |
| 43 | 120 | M72 | 180 | 35 | 4.79 |
| 50 | 145 | M90 | 220 | 50 | 9.9 |
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.
| 58 |
| 180 |
| M110 |
| 260 |
| 60 |
| 17.3 |
| 66 | 230 | M140 | 320 | 80 | 36.1 |
| 74 | 260 | M160 | 350 | 100 | 54.9 |
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