Standard: JIS B 1251
Available sizes: (Φ3.5) to Φ4 (4 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| (Φ3.5) | 6.1 | 1.8 | 2.35 | 1.2 | 6.5 | 2.5 | 1.1 | 11.9 | 2.65 | 1.3 |
| Φ2.5 | 3.1 | 1.05 | 1.2 | 0.7 | 3.4 | 1.3 | 0.6 | 6.3 | 1.4 | 0.8 |
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.
| Φ3 | 4.1 | 1.2 | 1.4 | 0.8 | 4.4 | 1.5 | 0.7 | 7.7 | 1.6 | 0.9 |
| Φ4 | 10.2 | 2.7 | 3.3 | 1.8 | 10.8 | 3.5 | 1.65 | 18.4 | 3.7 | 1.95 |
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