Standard: HG /T 20631
Available sizes: 15 to 40 (5 sizes)
| Size | P | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|
| 15 | 3/4 | 2 | 33.3 | 42.9 | 20.6 | 33.3 | 42.9 | 3.2 | 42.9 | 27 |
| 20 | 1-1/4 | 2 | 47.6 | 63.5 | 34.9 | 47.6 | 63.5 | 3.2 | 63.5 |
| 41.3 |
| 25 | 2 | 2 | 73 | 92.1 | 52.4 | 73 | 92.1 | 3.2 | 92.1 | 60.3 |
| 32 | 3 | 2 | 108 | 127 | 77.8 | 108 | 127 | 3.2 | 127 | 95.3 |
| 40 | 5 | 2 | 160.3 | 185.7 | 128.6 | 160.3 | 185.7 | 3.2 | 185.7 | 146.1 |
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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