Standard: IFI 136
Available sizes: 1/2 to 9/16 (7 sizes)
| Size | P | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 8 | 0.9830 | 2.250 | 1.0000 | 0.9100 | 2.750 | 3.000 | 1.0000 | 2.500 |
| 1/4 | 18 | 0.3026 | 0.875 | 0.3125 | 0.2712 | 1.031 | 1.281 | 0.3125 | 1.125 |
| 3/8 | 12 | 0.5495 | 1.375 | 0.5625 | 0.5016 |
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.
| 1.656 |
| 1.906 |
| 0.5625 |
| 1.625 |
| 5/16 | 14 | 0.4258 | 1.125 | 0.4375 | 0.3850 | 1.344 | 1.594 | 0.4375 | 1.375 |
| 5/8 | 6 | 1.4794 | 3.250 | 1.5000 | 1.3812 | 4.000 | 4.250 | 1.5000 | 3.500 |
| 7/16 | 10 | 0.7353 | 1.75 | 0.7500 | 0.6773 | 2.125 | 2.375 | 0.7500 | 2.000 |
| 9/16 | 7 | 1.2314 | 2.750 | 1.2500 | 1.1476 | 3.375 | 3.625 | 1.2500 | 3.000 |
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