Standard: GB /T 2234 - 1991
Available sizes: M4 to M8 (4 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal |
|---|---|---|---|---|---|---|
| M4 | 25 | 5.5 | 5.32 | 34 | 8 | 5 |
| M5 | 40 | 10 | 9.78 | 52 | 12 | 8 |
| M6 | 60 | 16 | 15.73 | 80 | 20 | 12 |
| M8 | 50 | 27 | 26.67 |
| 80 |
| 32 |
| 20 |
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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