Standard: GB /T 27 - 1988
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 | 13.35 | 12.65 | 35.38 | 35 | 25 | 24.948 | 12.78 | 13.22 | 36 | 13 |
| (M18) | 4.5 | 23.42 | 22.58 | — | 63.8 | 44 | 43.938 | — |
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.
| — |
| 65 |
| 23 |
| M10 | 2.0 | 9.29 | 8.71 | 23.67 | 23.16 | 17 | 16.957 | 8.82 | 9.18 | 24 | 9 |
| M12 | 2.5 | 11.35 | 10.65 | 29.67 | 29.16 | 21 | 20.948 | 10.78 | 11.22 | 30 | 11 |
| M16 | 3.5 | 17.35 | 16.65 | — | 45 | 32 | 31.938 | — | — | 46 | 17 |
| M20 | 5 | 26.42 | 25.58 | — | 73.1 | 50 | 49.938 | — | — | 75 | 26 |
| M6 | 1.25 | 5.24 | 4.76 | 12.73 | 12.57 | 9 | 8.964 | 4.85 | 5.15 | 13 | 5 |
| M8 | 1.75 | 7.29 | 6.71 | 17.73 | 17.57 | 13 | 12.957 | 6.82 | 7.18 | 18 | 7 |
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