Standard: GB /T 893.2 - 1986
Available sizes: 20 to 28 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 20 | 22.37 | 2.5 | 4.45 | 1.05 | 2 | 22.92 | 1 | 0.64 | 4.15 | 0.87 | 0.6 |
| 21 | 25.69 | 2.5 | 4.45 | 1.25 | 2 | 26.32 | 1.2 | 0.64 |
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.
| 4.15 |
| 1.07 |
| 0.6 |
| 22 | 27.69 | 2.8 | 4.45 | 1.25 | 2 | 28.32 | 1.2 | 0.745 | 4.15 | 1.07 | 0.7 |
| 24 | 31.85 | 3.2 | 5.05 | 1.25 | 2 | 32.6 | 1.2 | 0.845 | 4.75 | 1.07 | 0.8 |
| 25 | 34.15 | 3.2 | 5.05 | 1.25 | 2.5 | 34.9 | 1.2 | 0.845 | 4.75 | 1.07 | 0.8 |
| 26 | 37.55 | 3.6 | 5.85 | 1.56 | 2.5 | 38.3 | 1.5 | 0.945 | 5.55 | 1.35 | 0.9 |
| 28 | 39.55 | 3.6 | 5.85 | 1.56 | 2.5 | 40.3 | 1.5 | 0.945 | 5.55 | 1.35 | 0.9 |
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