Standard: GB /T 547
Available sizes: b1 to b7 (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| b1 | 65 | 70 | 19 | 25 | 4 | 100 | 1.2 | 45 | 20 |
| b2 | 82 | 90 | 26 | 34 | 5 | 135 | 2.35 | 60 | 24 |
| b3 | 106 | 124 | 34 | 42 | 7 | 183 |
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.
| 5.3 |
| 75 |
| 32 |
| b4 | 130 | 150 | 40 | 50 | 9 | 218 | 9.8 | 90 | 40 |
| b5 | 157 | 180 | 52 | 61 | 11 | 263 | 17.4 | 110 | 48 |
| b6 | 194 | 220 | 60 | 74 | 13 | 320 | 31.7 | 130 | 60 |
| b7 | 200 | 236 | 65 | 80 | 14 | 345 | 33.4 | 130 | 60 |
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