Standard: NF E 25
Available sizes: 3.2 to 4 (2 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB /T 12616.1 |
| ISO | ISO 15974 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 3.2 | 4.08 | 1.7 | 2.35 | 3.85 | 8.4 | 6.9 | 25 |
| 4 | 4.88 | 2 | 2.77 |
| 4.65 |
| 10.1 |
| 8.3 |
| 27 |
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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