3/8" NPT Thread Size
Complete thread specifications for 3/8 inch NPT threads. Common in pneumatic systems, fuel lines, and medium-pressure applications.
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NPT threads follow ASME B1.20.1 standard with 1:16 taper
Note: This page shows 3/8" NPT dimensions. Use the dropdown above to explore other sizes.
Thread Specifications
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3/8" NPT Thread Specifications
The 3/8 inch NPT thread strikes a balance between compact size and adequate flow capacity. With 18 TPI, it's commonly used in pneumatic systems, fuel distribution, and hydraulic applications where space is limited.
Key Dimensions
- Major Diameter: 0.6750" (17.15 mm)
- Minor Diameter: 0.6145" (15.61 mm)
- Threads Per Inch: 18 TPI
- Drill Tap Size: 37/64" (14.68 mm)
Common Applications
- Pneumatic cylinders and air valve connections
- Fuel and oil distribution lines
- Hydraulic power units and manifolds
- Compressor accessories and air dryers
- Automotive transmission cooler lines