Standard: GB 25 - 1976
Available sizes: (M14) to M8 (7 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| (M14) | 2.5 | 34.6 | 12.35 | 11.65 | 30 | 29.72 | 3.5 | 7 | 12 | 1 |
| (M18) | 4 | 57.7 | 20.42 | 19.55 | 50 | 49.66 | 5 | 12 | 20 |
| 1.5 |
| M10 | 2 | 21.9 | 8.29 | 7.71 | 19 | 18.72 | 2.5 | 4.5 | 8 | 0.6 |
| M12 | 2.5 | 27.7 | 10.29 | 9.71 | 24 | 23.72 | 3 | 6 | 10 | 1 |
| M16 | 3 | 41.6 | 15.35 | 14.65 | 36 | 35.66 | 4 | 9 | 15 | 1 |
| M20 | 5 | 75 | 26.42 | 25.58 | 65 | 64.6 | 5 | 16 | 26 | 1.5 |
| M8 | 1.5 | 16.2 | 6.24 | 5.76 | 14 | 13.76 | 2 | 3 | 6 | 0.4 |
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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