Note: The information contained here is for referance only of common standards and and may not accurately reflect actual product dimensions.
Please check the product details or ask if any dimension is critical
US Standard Taper Pipe Thread NPT
| Pipe Size (inches) |
Threads per Inch TPI – pitch |
Approximate Length of Thread(inches) | Approximate Number of Threads to be Cut | Approximate Total thread Makeup, Hand and Wrench(inches) | Nominal Outside Pipe Diameter OD (inches) |
Tap Drill (inches) |
| 1/16″ | 27 | 0.313 | ||||
| 1/8″ | 27 | 3/8 | 10 | 1/4 | 0.405 | R |
| 1/4″ | 18 | 5/8 | 11 | 3/8 | 0.540 | 7/16 |
| 3/8″ | 18 | 5/8 | 11 | 3/8 | 0.675 | 37/64 |
| 1/2″ | 14 | 3/4 | 10 | 7/16 | 0.840 | 23/32 |
| 3/4″ | 14 | 3/4 | 10 | 1/2 | 1.050 | 59/64 |
| 1″ | 11-1/2 | 7/8 | 10 | 9/16 | 1.315 | 1-5/32 |
| 1-1/4″ | 11-1/2 | 1 | 11 | 9/16 | 1.660 | 1-1/2 |
| 1-1/2″ | 11-1/2 | 1 | 11 | 9/16 | 1.900 | 1-47/64 |
| 2″ | 11-1/2 | 1 | 11 | 5/8 | 2.375 | 2-7/32 |
| 2-1/2″ | 8 | 1 1/2 | 12 | 7/8 | 2.875 | 2-5/8 |
| 3″ | 8 | 1 1/2 | 12 | 1 | 3.500 | 3-1/4 |
| 3-1/2″ | 8 | 1 5/8 | 13 | 1 1/16 | 4.000 | 3-3/4 |
| 4″ | 8 | 1 5/8 | 13 | 1 1/16 | 4.500 | 4-1/4 |
| 4 1/2″ | 8 | 5.000 | 4-3/4 | |||
| 5″ | 8 | 1 3/4 | 14 | 1 3/16 | 5.563 | 5-9/32 |
| 6″ | 8 | 1 3/4 | 14 | 1 3/16 | 6.625 | 6-11/32 |
| 8″ | 8 | 1 7/8 | 15 | 1 5/16 | 8.625 | |
| 10″ | 8 | 2 | 16 | 1 1/2 | 10.750 | |
| 12″ | 8 | 2 1/8 | 17 | 1 5/8 | 12.750 | |
| 14″ | 8 | 14.000 | ||||
| 16″ | 8 | 16.000 |