Standard: GB /T 305 - 2019
Available sizes: 13 to 28 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 305 |
| ISO | ISO 464 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 13 | 18.5 | 0.6 | 3 | 15 | 14.7 | 0.7 | 1.65 |
| 16 | 25.1 | 0.6 | 3 | 20.8 | 20.4 | 0.7 | 2 |
| 19 | 29.2 | 0.6 | 3 | 24.9 | 24.5 | 0.7 | 2 |
| 22 |
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.
| 34.7 |
| 1.02 |
| 3 |
| 27.9 |
| 27.5 |
| 1.12 |
| 3.25 |
| 24 | 39.7 | 1.02 | 3 | 32.9 | 32.5 | 1.12 | 3.25 |
| 26 | 44.6 | 1.02 | 3 | 37.8 | 37.4 | 1.12 | 3.25 |
| 28 | 46.3 | 1.02 | 3 | 39.5 | 39 | 1.12 | 3.25 |
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