Standard: GB /T 5627 - 2008
Available sizes: 10 to 8 (8 sizes)
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 10 | 20 | / | 18 | R 3/4 | NPT 3/4 | 102.5 | 32 |
| 12 | 25 | / | 21.5 | R 1 | NPT 1 | 106 | 41 |
| 14 | 32 | / | 24 | R 1-1/4 | NPT 1-1/4 | 111 | 46 |
| 16 |
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.
| 34 |
| / |
| 24 |
| R 1-1/4 |
| NPT 1-1/4 |
| 111 |
| 46 |
| 4 | 5 | 58 | 8.5 | R 1/8 | NPT 1/8 | 53.5 | 12 |
| 5 | 8 | 100 | 12.5 | R 1/4 | NPT 1/4 | 92 | 17 |
| 6 | 12 | 105 | 13 | R 3/8 | NPT 3/8 | 93.5 | 22 |
| 8 | 16 | 111 | 17 | R 1/2 | NPT 1/2 | 95 | 27 |
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