Standard: UNI 7474 - 1975
Available sizes: (M7) to M8 (5 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 | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| (M7) | 2 | 22 | 19.6 | 1.5 |
| 14 |
| 7 |
| 19.3 |
| M4 | 0.8 | 8 | 1.13 | / | 5.4 | 2.5 | / |
| M5 | 1 | 11 | 2.64 | / | 7 | 3.5 | / |
| M6 | 1.5 | 17 | 9.48 | 1.25 | 10 | 5 | 9.36 |
| M8 | 2 | 24 | 25.5 | 1.5 | 15 | 8 | 25 |
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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