Standard: ZQ 4343 - 1997
Available sizes: 210 to 250 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 210 | 5 | 4 | 315 | 4.88 | 233.7 | 231.28 |
| 220 | 5 | 4 | 345 | 4.88 | 254 | 251.19 |
| 230 | 5 | 5 | 375 | 4.88 | 277 | 274.19 |
| 240 | 5 | 5 | 400 | 4.88 | 297 | 294.19 |
| 250 |
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.
| 5 |
| 5 |
| 435 |
| 4.88 |
| 317 |
| 314.19 |
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