Standard: CB /T 679 - 2000
Available sizes: 31~40 to 61~80 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| 31~40 | 30~38 | 0.6 | 0.032 | 1 | 14 | 0.8 |
| 41~50 | 48~65 | 0.6 | 0.040 | 1 | 14 | 0.8 |
| 51~60 | 80~90 | 0.6 | 0.056 | 0.6 | 14 | 1 |
| 61~80 | 120~130 | 0.6 | 0.074 |
| 0.25 |
| 14 |
| 1 |
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.
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