Standard: GB /T 6172.2 - 2016
Available sizes: M10 to M8 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 6172.2 |
| NF | NF E 25-412 |
| DIN | DIN 985 |
| ISO | ISO 10511 |
| UNI | UNI 7474 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|
| M10 | 3.5 | 45.00 | 46.00 | 50.85 | 22.20 | 32.40 | 30.00 | 13.90 | 11.12 | 42.80 | 20.10 |
| M12 | 4 | 53.80 | 55.00 | 60.79 | 25.50 | 38.90 | 36.00 | 16.90 | 13.52 | 51.10 | 23.40 |
| M3 | 0.7 | 6.78 | 7.00 | 7.66 | 5.00 | 4.60 | 4.00 | 1.95 | 1.56 | 5.90 | 4.52 |
| M4 | 1 | 9.78 | 10.00 | 11.05 | 6.00 | 6.75 | 6.00 | 2.90 | 2.32 | 8.90 | 5.52 |
| M5 | 1.5 | 15.73 | 16.00 | 17.77 | 8.56 | 10.80 | 10.00 | 4.70 | 3.76 | 14.60 | 7.98 |
| M6 | 2 | 20.67 | 21.00 | 23.35 | 11.32 | 15.10 | 14.00 | 6.42 | 5.14 | 19.60 | 10.22 |
| M8 | 2.5 | 29.16 | 30.00 | 32.95 | 14.90 | 21.60 | 20.00 | 9.10 | 7.28 | 27.70 | 13.10 |
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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