Standard: QJ 2963.4 - 1997
Available sizes: 2 to 4 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 2 | 2.6 | 0.73 | 1.3 | 2.85 | 0.65 | 0.33 | 0.57 | 1.63 |
| 2.5 | 4.1 | 1.2 | 2.2 | 4.4 | 1.1 | 0.55 | 1 | 2.75 |
| 3 | 6.1 | 1.7 | 3.2 | 6.68 |
| 1.6 |
| 0.8 |
| 1.5 |
| 4 |
| 4 | 10.2 | 2.75 | 5.2 | 10.9 | 2.6 | 1.3 | 2.45 | 6.5 |
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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