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 | 4.3 | 16 | 11 | 21 | 16 | 40 | 31 | 80 | 60 | 50 |
| 16 | 32000 | 5.4 | 25 | 13.5 | 26 | 25 | 55 |
| 56 |
| 110 |
| 80 |
| 80 |
| 20 | 80000 | 8.4 | 36 | 22 | 41 | 40 | 76 | 88 | 170 | 120 | 125 |
| 25 | 200000 | 11.4 | 50 | 33 | 61 | 63 | 112 | 130 | 265 | 180 | 200 |
| 32 | 385000 | 12.4 | 63 | 45 | 91 | 90 | 160 | 190 | 345 | 250 | 265 |
| 40 | 630000 | 15.4 | 80 | 52 | 112 | 110 | 200 | 240 | 410 | 310 | 320 |
| 50 | 785000 | 15.4 | 80 | 62 | 132 | 125 | 220 | 270 | 570 | 345 | 385 |
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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