Standard: ISO 7040 - 1997
Available sizes: M10 to M8 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 889.1 |
| NF | NF E 25-409 |
| DIN | DIN EN ISO 7040 |
| ISO | ISO 7040 |
| UNI | UNI 7473 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|
| M10 | 3.5 | 45 | 46 | 50.85 | 32.6 | 32.40 | 30.00 | 24.3 | 19.44 | 42.75 | 30.1 |
| M12 | 4 | 53.8 | 55 | 60.79 | 38.9 | 38.90 | 36.00 | 29.4 | 23.52 | 51.11 | 36.4 |
| M3 | 0.7 | 6.78 | 7 | 7.66 | 6.00 | 4.60 | 4.00 | 2.9 | 2.32 | 5.88 | 5.52 |
| M4 | 1 | 9.78 | 10 | 11.05 | 8.00 | 6.75 | 6.00 | 4.9 | 3.92 | 8.88 | 7.42 |
| M5 | 1.5 | 15.73 | 16 | 17.77 | 11.9 | 10.80 | 10.00 | 8.04 | 6.43 | 14.63 | 11.2 |
| M6 | 2 | 20.67 | 21 | 23.36 | 17.00 | 15.10 | 14.00 | 12.1 | 9.68 | 19.64 | 15.9 |
| M8 | 2.5 | 29.16 | 30 | 32.95 | 22.8 | 21.60 | 20.00 | 16.9 | 13.52 | 27.70 | 20.7 |
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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