Standard: GB 931 - 1988
Available sizes: M4 to M6 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M4 | 5.8 | 9.5 | 8 | 5 | 5.09 | 5.74 | 2.72 | 1.25 | 1 | 2.6 | 4.91 |
| M5 | 9.2 | 13 | 11 | 8 | 8.11 | 9.1 | 3.26 | 1.75 |
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.
| 1.5 |
| 3.1 |
| 7.89 |
| M6 | 11 | 16 | 13 | 10 | 10.11 | 10.9 | 3.26 | 2.05 | 1.8 | 3.1 | 9.89 |
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