4" NPT Thread Specifications
Complete dimensions for 4" NPT pipe thread. TPI: 8, Pitch: 0.125" (3.175 mm).
Thread Dimensions
| Designation | 4" NPT |
| Nominal Pipe Size | 4" |
| TPI | 8 |
| Pitch | 0.125" (3.175 mm) |
| Outside Diameter | 4.5" (114.3 mm) |
| Pitch Diameter | 4.4188" (112.24 mm) |
| Minor Diameter | 4.3466" (110.41 mm) |
| Taper Angle | 1.7899° (1:16 taper ratio) |
| Thread Depth | 0.0866" (2.2 mm) |
Tap Drill Size
Tap drill: 4.3466" (110.4 mm)
Common Applications
- Plumbing connections
- Gas piping
- Hydraulic fittings
- Pneumatic connections