Standard: GB 56 - 1988
Available sizes: (M18) to M24 (5 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M18) | 2.5 | 136.3 | 33 | 37.29 | 35 | 23.7 | 22 | 26.72 | 34 | 31.4 | 33.4 |
| (M22) | 4 | 572.6 | 53.8 | 60.79 | 55 | 38.9 | 36 | 42.48 | 55 | 51.1 | 53.1 |
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 | 2.5 | 66.33 | 26.16 | 29.56 | 28 | 19.5 | 18 | 21.73 | 27 | 24.8 | 27.16 |
| M20 | 3 | 237.7 | 40 | 45.2 | 42 | 29.1 | 27 | 32.32 | 41 | 38 | 40.4 |
| M24 | 5 | 1495 | 73.1 | 82.6 | 75 | 51.8 | 48 | 58.48 | 75 | 69.4 | 73.1 |
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