Standard: GB /T 21934 - 2008
Available sizes: M12 to M20 (3 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| M12 | 16.30 | 12.30 | 11.1 | 15.90 | 27.80 | 148 | 226~294 | 27.00 | 28 |
| M16 | 23.00 | 17.20 | 15.6 | 22.20 | 36.60 | 304 | 637~852 | 35.70 | 35 |
| M20 | 32.6 |
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.
| 27 |
| 25.4 |
| 31.8 |
| 54.9 |
| 637 |
| 1598~2156 |
| 53.5 |
| 50 |
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