Standard: GOST 6402 - 1970
Available sizes: (3) to 4 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (3) | 4.1 | 0.875 | 1.125 | 0.72 | 1.2 | 4.4 | 0.8 | 1.075 | 1 | 0.88 | 1.325 |
| (4) | 8.2 | 1.875 | 2.125 | 1.475 | 2.5 | 8.78 | 1.6 | 2.375 | 2 | 1.725 | 2.625 |
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.
| 2 | 2.6 | 0.53 | 0.67 | 0.53 | 0.8 | 2.85 | 0.6 | 0.72 | 0.6 | 0.67 | 0.88 |
| 2.5 | 3.1 | 0.72 | 0.88 | 0.72 | 1 | 3.4 | 0.8 | 0.875 | 0.8 | 0.88 | 1.125 |
| 3 | 5.1 | 1.075 | 1.325 | 0.875 | 1.2 | 5.4 | 1 | 1.075 | 1.2 | 1.125 | 1.325 |
| 3.5 | 6.1 | 1.275 | 1.525 | 1.075 | 1.6 | 6.68 | 1.2 | 1.475 | 1.4 | 1.325 | 1.725 |
| 4 | 7.2 | 1.875 | 2.125 | 1.475 | 2 | 7.78 | 1.6 | 1.875 | 2 | 1.725 | 2.125 |
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