Standard: GB 1021 - 1978
Available sizes: 10 to 8 (6 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 10 | 20.1 | 15 | 16.5 | 22 | 22.3 | 20.62 | 28 | 14 | 16 | 27.48 | 21.7 |
| 12 | 24.1 | 18 | 19 | 26 | 26.3 | 24.62 | 34 |
| 17 |
| 20 |
| 33.38 |
| 25.7 |
| 4 | 5.1 | 4.5 | 6.8 | 8 | 8.3 | 5.4 | 8 | 4 | 5 | 7.64 | 7.7 |
| 5 | 8.1 | 7 | 8 | 11 | 11.3 | 8.46 | 13 | 6.5 | 7 | 12.57 | 10.7 |
| 6 | 12.1 | 10 | 10.5 | 15 | 15.3 | 12.53 | 18 | 9 | 10 | 17.57 | 14.7 |
| 8 | 16.1 | 12.5 | 13 | 18 | 18.3 | 16.53 | 23 | 11.5 | 12 | 22.48 | 17.7 |
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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