Standard: TB /T 55 - 1993
Available sizes: 10 to 8 (5 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 10 | 19.89 | 4 | 2 | 5 | 19.68 | 32 | 5*40 | 20 | 4 | 6 |
| 12 | 24.89 | 4 | 2 | 6.3 | 24.68 | 40 | 6.3*50 | 25 | 5 | 8 |
| 16 | 27.89 | 4 |
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 |
| 6.3 |
| 27.68 |
| 42 |
| 6.3*50 |
| 28 |
| 5 |
| 8 |
| 6 | 7.92 | 2 | 1 | 3.2 | 7.77 | 14 | 3.2*20 | 8 | 3 | 5 |
| 8 | 11.905 | 2 | 1 | 4 | 11.725 | 20 | 4*30 | 12 | 3.5 | 5 |
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