Standard: GB /T 1338 - 1988
Available sizes: (M14) to M8 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M14) | 1.5 | 29.67 | 30 | 15.22 | 14.78 | 23.7 | 23.6 | 7.68 | 7.32 | 15 | 7.5 |
| M10 | 1.5 | 18.67 | 19 | 10.18 | 9.82 | 15.5 | 15.4 | 5.15 |
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.
| 4.85 |
| 10 |
| 5 |
| M12 | 1.5 | 23.67 | 24 | 12.22 | 11.78 | 19.6 | 19.5 | 6.68 | 6.32 | 12 | 6.5 |
| M16 | 1.5 | 31.61 | 32 | 16.22 | 15.78 | 25.7 | 25.6 | 8.18 | 7.82 | 16 | 8 |
| M8 | 1.5 | 13.73 | 14 | 8.18 | 7.82 | 11 | 10.9 | 3.65 | 3.35 | 8 | 3.5 |
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