Standard: ASME B 18.3 - 2003
Available sizes: 1/2 to 5/8 (6 sizes)
| Standard Body | Standard Number |
|---|---|
| GB | GB 5281 |
| ISO | ISO 7379 |
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1/2 | 9 | 0.469 | 0.625 | 1.246 | 1.750 | 7/8 |
| 0.8750 |
| 0.750 |
| 0.735 |
| 1.248 |
| 1.723 |
| 1/4 | 20 | 0.117 | 0.156 | 0.3085 | 0.438 | 1/4 | 0.2500 | 0.219 | 0.209 | 0.3105 | 0.419 |
| 3/4 | 6 | 0.937 | 1.250 | 1.996 | 2.750 | 1-1/2 | 1.5000 | 1.250 | 1.230 | 1.998 | 2.720 |
| 3/8 | 11 | 0.281 | 0.375 | 0.746 | 1.000 | 5/8 | 0.6250 | 0.500 | 0.490 | 0.748 | 0.977 |
| 5/16 | 16 | 0.188 | 0.250 | 0.496 | 0.750 | 3/8 | 0.3750 | 0.312 | 0.302 | 0.498 | 0.729 |
| 5/8 | 7 | 0.750 | 1.000 | 1.746 | 2.375 | 1-1/4 | 1.2500 | 1.125 | 1.105 | 1.748 | 2.345 |
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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