Standard: GB 28 - 1976
Available sizes: (M14) to M8 (8 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M14) | 3 | 0.5 | 5 | 31.66 | 13 | 25 | 24.955 | 12.65 | 5.48 | 32 | 13.35 |
| (M18) | 4.5 | 1 | 8 | 54.6 | 23 | 44 | 43.95 |
| 22.58 |
| 8.58 |
| 55 |
| 23.42 |
| M10 | 2 | 0.25 | 4 | 21.72 | 9 | 17 | 16.965 | 8.71 | 4.48 | 22 | 9.29 |
| M12 | 2.5 | 0.5 | 4 | 26.72 | 11 | 21 | 20.955 | 10.65 | 4.48 | 27 | 11.35 |
| M16 | 3.5 | 0.5 | 6 | 40.66 | 17 | 32 | 31.95 | 16.65 | 6.48 | 41 | 17.35 |
| M20 | 5 | 1 | 8 | 64.6 | 26 | 50 | 49.95 | 25.58 | 8.58 | 65 | 26.42 |
| M6 | 1.25 | 0.25 | 2 | 11.76 | 5 | 9 | 8.97 | 4.76 | 2.4 | 12 | 5.24 |
| M8 | 1.75 | 0.25 | 3 | 16.76 | 7 | 13 | 12.965 | 6.71 | 3.4 | 17 | 7.29 |
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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