Standard: JB /T 7934 - 1999
Available sizes: 20 to 40 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 20 | 47 | 17 | 90 | M6 | 4 | 37 | 31 | 0.33 | 260 | 21.7 | 30 |
| 22 | 55 | 17 | 96 | M6 | 5 | 37 | 31 | 0.49 |
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.
| 256 |
| 21.7 |
| 35 |
| 25 | 60 | 17 | 106 | M6 | 6 | 37 | 31 | 0.81 | 246 | 21.7 | 45 |
| 28 | 75 | 41 | 134 | M8 | 6 | 46 | 38 | 1.86 | 283 | 25.3 | 80 |
| 30 | 85 | 41 | 138 | M8 | 7 | 46 | 38 | 2.54 | 270 | 25.3 | 90 |
| 35 | 95 | 41 | 141 | M8 | 8 | 46 | 38 | 3.58 | 261 | 25.3 | 105 |
| 40 | 110 | 83 | 128 | M10 | 7 | 60 | 50 | 5.1 | 244 | 33.4 | 140 |
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