Standard: GB /T 39949.1
Available sizes: 12 to 50 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 12 | 12500 | 40.125 | 39.875 | 16 | 16.29 | 16 | 16.043 | / | 40 | 36 | 16.56 |
| 16 | 32000 | 55.15 | 54.85 | 25 | 25.3 | 25 | 25.052 |
| / |
| 55 |
| 56 |
| 25.63 |
| 20 | 80000 | 76.15 | 75.85 | 40 | 40.31 | 40 | 40.062 | / | 76 | 90 | 40.7 |
| 25 | 200000 | 112.175 | 111.825 | 63 | 63.34 | 63 | 63.074 | 1×45° | 112 | 140 | 63.8 |
| 32 | 320000 | 140.2 | 139.8 | 80 | 80.36 | 80 | 80.074 | 2×45° | 140 | 170 | 80.82 |
| 40 | 500000 | 180.2 | 179.8 | 100 | 100.38 | 100 | 100.087 | 2×45° | 180 | 210 | 100.92 |
| 50 | 800000 | 230.23 | 229.77 | 125 | 125.46 | 125 | 125.1 | 5×45° | 230 | 270 | 126.09 |
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.
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