Standard: GB /T 93 - 1987
Available sizes: 2 to 6 (6 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 2 | 2.6 | 0.033 | 0.73 | 0.57 | 2.85 | 0.65 | 1.3 | 1.63 | 0.57 | 0.73 |
| 2.5 | 4.1 | 0.15 | 1.2 | 1 | 4.4 | 1.1 | 2.2 | 2.75 | 1 | 1.2 |
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.
| 3 | 6.1 | 0.47 | 1.7 | 1.5 | 6.68 | 1.6 | 3.2 | 4 | 1.5 | 1.7 |
| 4 | 10.2 | 2.06 | 2.75 | 2.45 | 10.9 | 2.6 | 5.2 | 6.5 | 2.45 | 2.75 |
| 5 | 14.2 | 5.51 | 3.8 | 3.4 | 14.9 | 3.6 | 7.2 | 9 | 3.4 | 3.8 |
| 6 | 18.2 | 10.98 | 4.7 | 4.3 | 19.04 | 4.5 | 9 | 11.25 | 4.3 | 4.7 |
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