Standard: GB /T 1230 - 2006
Available sizes: (22) to 20 (4 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 1230 |
| ISO | ISO 7416 |
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| (22) | 31 | 75.42 | 5 | 4.5 | 31.62 | 54.1 | 35.84 |
| 36.64 |
| 56 |
| 5.8 |
| 12 | 17 | 23.4 | 4 | 3.5 | 17.43 | 31.4 | 19.23 | 20.03 | 33 | 4.8 |
| 16 | 23 | 43.34 | 5 | 4.5 | 23.52 | 40.4 | 26.32 | 27.12 | 42 | 5.8 |
| 20 | 28 | 66.52 | 5 | 4.5 | 28.52 | 50.1 | 32.84 | 33.64 | 52 | 5.8 |
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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