Standard: GB /T 2171 - 1991
Available sizes: 10 to 8 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 10 | 36 | 12.5 | 17.5 | 19.5 | 19.78 | 28 | M24 | 18 | 6.4 | 18.5 | 26 |
| 4 | 10 | 3.5 | 6 | — | — | 9 | M5 |
| — |
| — |
| — |
| 6 |
| 5 | 16 | 5 | 8 | 6.9 | 7 | 12 | M8 | 7.5 | 3.1 | 6.3 | 10 |
| 6 | 20 | 7.5 | 11.5 | 10 | 10.1 | 18 | M12 | 10.5 | 4.2 | 9.5 | 14 |
| 8 | 30 | 10.5 | 15 | 17.5 | 17.62 | 25 | M20 | 16 | 5.4 | 16.5 | 22 |
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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