Standard: GB /T 894.2 - 1986
Available sizes: 20 to 29 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 20 | 19.5 | 1.24 | 1.1 | 1.05 | 0.87 | 19.63 | 19.08 | 20 | 19.87 | 1 | 2 |
| 21 | 22.2 | 1.44 | 1.3 | 1.25 | 1.07 | 22.41 | 21.78 | 22.9 |
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.
| 22.69 |
| 1.2 |
| 2 |
| 22 | 24.2 | 1.44 | 1.3 | 1.25 | 1.07 | 24.41 | 23.78 | 24.9 | 24.69 | 1.2 | 2 |
| 24 | 26.9 | 1.44 | 1.3 | 1.25 | 1.07 | 27.11 | 26.48 | 27.6 | 27.39 | 1.2 | 2 |
| 25 | 29.6 | 1.44 | 1.3 | 1.25 | 1.07 | 29.81 | 29.18 | 30.3 | 30.05 | 1.2 | 2.5 |
| 26 | 32.2 | 1.84 | 1.7 | 1.56 | 1.35 | 32.45 | 31.7 | 33 | 32.75 | 1.5 | 2.5 |
| 28 | 34.2 | 1.84 | 1.7 | 1.56 | 1.35 | 34.45 | 33.7 | 35 | 34.75 | 1.5 | 2.5 |
| 29 | 35.2 | 1.84 | 1.7 | 1.56 | 1.35 | 35.45 | 34.7 | 36 | 35.75 | 1.5 | 2.5 |
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