Standard: JB /T 7934 - 1999
Available sizes: 20 to 35 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 20 | 47 | 95 | 200 | 34 | M6×20 | 17 | 22 | 30 | 0.32 | 28 | 5 |
| 22 | 50 | 110 | 215 | 34 | M6×20 | 17 | 22 | 36 |
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.
| 0.45 |
| 28 |
| 6 |
| 24 | 55 | 100 | 190 | 34 | M6×20 | 17 | 22 | 36 | 0.54 | 28 | 6 |
| 25 | 60 | 110 | 190 | 34 | M6×20 | 17 | 22 | 48 | 0.84 | 28 | 8 |
| 28 | 65 | 105 | 190 | 34 | M6×20 | 17 | 22 | 48 | 0.96 | 28 | 8 |
| 30 | 80 | 130 | 210 | 41 | M8×25 | 20 | 25 | 77 | 1.93 | 33 | 7 |
| 32 | 90 | 125 | 190 | 41 | M8×25 | 20 | 25 | 88 | 2.7 | 33 | 8 |
| 35 | 95 | 140 | 205 | 41 | M8×25 | 20 | 25 | 100 | 3.18 | 33 | 9 |
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