Standard: GB 109 - 1986
Available sizes: (Φ3.5) to Φ4 (5 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (Φ3.5) | 8.1 | 3 | 2.6 | 7.9 | 16.35 | 15.65 | 0.5 |
| Φ2 | 2.56 | 1.4 | 1 | 2.44 | 5.24 | 4.76 | 0.1 |
| Φ2.5 | 3.58 | 1.8 | 1.4 | 3.42 | 7.29 | 6.71 | 0.3 |
| Φ3 | 5.08 | 2.2 | 1.8 |
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.
| 4.92 |
| 10.29 |
| 9.71 |
| 0.3 |
| Φ4 | 10.1 | 3.44 | 2.96 | 9.9 | 20.42 | 19.58 | 0.5 |
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