Standard: QC /T 383 - 2013
Available sizes: NPT1/2 to NPT3/8 (3 sizes)
| Size | P | e | r | k_max | k_min | s_max | s_min | ds_max | ds_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|---|---|---|---|
| NPT1/2 | 34 | 22*8 | 22 | 24 | 32 | 33.38 | 37.72 | 24 | 22.14 | 35 | 5 |
| NPT3/4 | 27 | 30*12 | 30 | 24 | 33 | 26.67 | 30.14 |
| 32 |
| 30.14 |
| 37 |
| 8 |
| NPT3/8 | 24 | 12*5 | 12 | 19 | 25 | 23.67 | 26.75 | 13 | 12.12 | 27.5 | 2.5 |
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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