Standard: JB /T 6687 - 1993
Available sizes: M10 to M8 (7 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M10 | 2.5 | 2.75 | 3 | 23 | 23.26 | 21.9 | 21.82 | 24 | 23.79 | 27.12 | 22.74 |
| M12 | 3 | 4.2 | 4.5 | 34 | 34.31 | 29 | 28.92 | 32 | 31.75 | 36.2 | 33.69 |
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.
| M16 | 3 | 5.2 | 5.5 | 41 | 41.31 | 36 | 35.9 | 41 | 40.75 | 46.46 | 40.69 |
| M20 | 3 | 7.14 | 7.5 | 49 | 49.31 | 43 | 42.9 | 46 | 45.75 | 52.16 | 48.69 |
| M24 | 3 | 8.14 | 8.5 | 57 | 57.37 | 49 | 48.9 | 55 | 54.7 | 62.36 | 56.63 |
| M6 | 1.25 | 1.15 | 1.4 | 11 | 11.21 | 9.4 | 9.34 | 10 | 9.85 | 11.23 | 10.79 |
| M8 | 1.75 | 2.25 | 2.5 | 17 | 17.21 | 13.50 | 13.43 | 14 | 13.82 | 15.75 | 16.79 |
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