Standard: GB 951 - 1986
Available sizes: (4.5) to 4 (6 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (4.5) | 3.5 | 5.95 | 5.39 | 19.48 | 5.8 | 9.64 | 10 | 10.3 | 0.5 | 20 | 4 |
| 2 | 1 | 1.52 | 1.14 | 4.7 | 1.4 | 2.25 | 2.5 |
| 2.7 |
| 0.2 |
| 5 |
| 1 |
| 2.5 | 1.4 | 2.13 | 1.6 | 6.64 | 2 | 3.2 | 3.5 | 4.2 | 0.4 | 7 | 2 |
| 3 | 1.8 | 3.13 | 2.58 | 8.64 | 2.7 | 4.2 | 4.5 | 5.2 | 0.4 | 9 | 2 |
| 3.5 | 2.2 | 3.36 | 2.8 | 10.57 | 3.2 | 5.2 | 5.5 | 6.7 | 0.4 | 11 | 3 |
| 4 | 2.8 | 4.46 | 3.87 | 13.57 | 4 | 6.64 | 7 | 7.8 | 0.5 | 14 | 3 |
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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