Standard: JB /T 14721
Available sizes: M10 to M8 (6 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| M10 | 2.5 | 29.16 | 32.95 | 26 | 21.6 | 20 | 10.9 | 30 | 27.7 | 16.9 |
| M3 | 0.7 | 6.78 | 7.66 | 5.6 | 4.6 | 4 | 2.2 | 7 | 5.9 |
| 4 |
| M4 | 1 | 9.78 | 11.05 | 8.5 | 6.75 | 6 | 3 | 10 | 8.9 | 5.4 |
| M5 | 1.5 | 15.73 | 17.77 | 13 | 10.8 | 10 | 4.8 | 16 | 14.6 | 8.04 |
| M6 | 2 | 20.67 | 23.36 | 18.2 | 15.1 | 14 | 7.8 | 21 | 19.6 | 12.1 |
| M8 | 2.5 | 26.16 | 29.56 | 23.4 | 19.5 | 18 | 9.7 | 27 | 24.9 | 15.1 |
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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