Standard: GB /T 18230.4 - 2000
Available sizes: (M12) to M20 (4 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 18230.4 |
| ISO | ISO 7414 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| (M12) | 2 | 27 | 0.2 | 29.56 | 14.8 | 17.3 |
| 16 |
| 11.28 |
| 0.8 |
| 24.9 |
| 14.1 |
| (M22) | 4 | 60 | 0.2 | 66.44 | 31 | 38.9 | 36 | 23.52 | 0.8 | 55.9 | 29.4 |
| M16 | 2.5 | 36 | 0.2 | 39.55 | 19.4 | 23.8 | 22 | 14.48 | 0.8 | 33.3 | 18.1 |
| M20 | 3 | 46 | 0.2 | 50.85 | 23.8 | 29.1 | 27 | 18 | 0.8 | 42.8 | 22.5 |
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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