Standard: TB /T 777 - 2005
Available sizes: M12 to M36 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M12 | 6 | 23.57 | 24 | 18.5 | 27.7 | 1.5 | 13.57 | 3 | 18 | 13.3 | 15 |
| M18 | 10 | 29.48 | 30 | 24.5 | 34.6 | 2 | 18.83 | 3 | 18 | 18.5 | 15 |
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.
| M20 |
| 13 |
| 33 |
| 34 |
| 27.5 |
| 39.2 |
| 2 |
| 21.83 |
| 5 |
| 18 |
| 21.5 |
| 15 |
| M24 | 20 | 45 | 46 | 36.5 | 53.1 | 2 | 31.99 | 5 | 20 | 31.6 | 17 |
| M27 | 32 | 63.8 | 65 | 56.5 | 75 | 2 | 51.89 | 5 | 27 | 51.5 | 22 |
| M33 | 40 | 68.8 | 70 | 60.5 | 80.8 | 2 | 55.46 | 5 | 27 | 55 | 22 |
| M36 | 50 | 79.8 | 81 | 72.5 | 93.1 | 2 | 65.46 | 5 | 27 | 65 | 22 |
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