Standard: GB 891 - 1986
Available sizes: 20 to 30 (5 sizes)
| Size | P | e | r | s_max | s_min | ds_max | ds_min | ds_nominal |
|---|---|---|---|---|---|---|---|---|
| 20 | 16 | M5*12 | 0.5 | 4 | 3.7 | 2.1 | 11 | 5.5 |
| 22 | 20 | M5*12 | 0.5 | 4 | 3.7 | 2.1 | 11 | 5.5 |
| 25 | 25 | M6*16 | 1 | 5 | 4.7 |
| 3.2 |
| 13 |
| 6.6 |
| 28 | 30 | M6*16 | 1 | 5 | 4.7 | 3.2 | 13 | 6.6 |
| 30 | 35 | M6*16 | 1 | 5 | 4.7 | 3.2 | 13 | 6.6 |
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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